rename: kafka → samsa

Full project rename from kafka to samsa (after Gregor Samsa, who
woke one morning from uneasy dreams to find himself transformed).

- Module: github.com/metamorphosis-dev/kafka → samsa
- Binary: cmd/kafka/ → cmd/samsa/
- CSS: kafka.css → samsa.css
- UI: all 'kafka' product names, titles, localStorage keys → samsa
- localStorage keys: kafka-theme → samsa-theme, kafka-engines → samsa-engines
- OpenSearch: ShortName, LongName, description, URLs updated
- AGPL headers: 'kafka' → 'samsa'
- Docs, configs, examples updated
- Cache key prefix: kafka: → samsa:

internal/engines/arxiv.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -28,7 +28,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 const (

internal/engines/arxiv_test.go

@@ -6,7 +6,7 @@ import (
 	"strings"
 	"testing"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestArxivEngine_Search(t *testing.T) {

internal/engines/bing.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -28,7 +28,7 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // BingEngine searches Bing via the public Bing API.

internal/engines/bing_images.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -18,7 +18,7 @@ import (
 	"net/url"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // BingImagesEngine searches Bing Images via their public RSS endpoint.

internal/engines/bing_test.go

@@ -7,7 +7,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestBingEngine_EmptyQuery(t *testing.T) {

internal/engines/brave.go

@@ -9,7 +9,7 @@ import (
 	"regexp"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 type BraveEngine struct {

internal/engines/braveapi.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -27,7 +27,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // BraveEngine implements the Brave Web Search API.

internal/engines/braveapi_test.go

@@ -5,7 +5,7 @@ import (
 	"net/http"
 	"testing"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestBraveEngine_GatingAndHeader(t *testing.T) {

internal/engines/crossref.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -27,7 +27,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 type CrossrefEngine struct {

internal/engines/crossref_test.go

@@ -5,7 +5,7 @@ import (
 	"net/http"
 	"testing"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestCrossrefEngine_Search(t *testing.T) {

internal/engines/ddg_images.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -19,7 +19,7 @@ import (
 	"strconv"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // DuckDuckGoImagesEngine searches DuckDuckGo Images via their vql API.

internal/engines/duckduckgo.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -25,7 +25,7 @@ import (
 	"net/url"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // DuckDuckGoEngine searches DuckDuckGo's Lite/HTML endpoint.

internal/engines/duckduckgo_parse.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -21,7 +21,7 @@ import (
 	"net/url"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // parseDuckDuckGoHTML parses DuckDuckGo Lite's HTML response for search results.

internal/engines/duckduckgo_test.go

@@ -7,7 +7,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestDuckDuckGoEngine_EmptyQuery(t *testing.T) {

internal/engines/engine.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -19,7 +19,7 @@ package engines
 import (
 	"context"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // Engine is a Go-native implementation of a search engine.

internal/engines/factory.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -21,7 +21,7 @@ import (
 	"os"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/config"
+	"github.com/metamorphosis-dev/samsa/internal/config"
 )
 
 // NewDefaultPortedEngines returns the Go-native engine registry.

internal/engines/github.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -27,7 +27,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // GitHubEngine searches GitHub repositories and code via the public search API.

internal/engines/github_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestGitHubEngine_EmptyQuery(t *testing.T) {

internal/engines/google.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -25,13 +25,13 @@ import (
 	"regexp"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // googleUserAgent is an honest User-Agent identifying the metasearch engine.
 // Using a spoofed GSA User-Agent violates Google's Terms of Service and
 // risks permanent IP blocking.
-var googleUserAgent = "Kafka/0.1 (compatible; +https://github.com/metamorphosis-dev/kafka)"
+var googleUserAgent = "Kafka/0.1 (compatible; +https://github.com/metamorphosis-dev/samsa)"
 
 type GoogleEngine struct {
 	client *http.Client

internal/engines/html_helpers.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify

internal/engines/planner.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -20,7 +20,7 @@ import (
 	"os"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 var defaultPortedEngines = []string{

internal/engines/qwant.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -26,7 +26,7 @@ import (
 	"net/url"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 	"github.com/PuerkitoBio/goquery"
 )
 

internal/engines/qwant_images.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -18,7 +18,7 @@ import (
 	"net/url"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // QwantImagesEngine searches Qwant Images via the v3 search API.

internal/engines/qwant_lite_test.go

@@ -5,7 +5,7 @@ import (
 	"net/http"
 	"testing"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestQwantEngine_WebLite(t *testing.T) {

internal/engines/qwant_test.go

@@ -5,7 +5,7 @@ import (
 	"net/http"
 	"testing"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestQwantEngine_Web(t *testing.T) {

internal/engines/reddit.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -26,7 +26,7 @@ import (
 	"net/url"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 // RedditEngine searches Reddit posts via the public JSON API.

internal/engines/reddit_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestRedditEngine_EmptyQuery(t *testing.T) {

internal/engines/stackoverflow.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -27,7 +27,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 const stackOverflowAPIBase = "https://api.stackexchange.com/2.3"

internal/engines/stackoverflow_test.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -23,7 +23,7 @@ import (
 	"net/http/httptest"
 	"testing"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestStackOverflow_Name(t *testing.T) {

internal/engines/wikipedia.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -26,7 +26,7 @@ import (
 	"net/url"
 	"strings"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 type WikipediaEngine struct {
@@ -108,7 +108,7 @@ func (e *WikipediaEngine) Search(ctx context.Context, req contracts.SearchReques
 	// Wikimedia APIs require a descriptive User-Agent.
 	httpReq.Header.Set(
 		"User-Agent",
-		"gosearch-go/0.1 (compatible; +https://github.com/metamorphosis-dev/kafka)",
+		"gosearch-go/0.1 (compatible; +https://github.com/metamorphosis-dev/samsa)",
 	)
 	// Best-effort: hint content language.
 	if req.Language != "" && req.Language != "auto" {

internal/engines/wikipedia_test.go

@@ -5,7 +5,7 @@ import (
 	"net/http"
 	"testing"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestWikipediaEngine_Search(t *testing.T) {

internal/engines/youtube.go

@@ -1,4 +1,4 @@
-// kafka — a privacy-respecting metasearch engine
+// samsa — a privacy-respecting metasearch engine
 // Copyright (C) 2026-present metamorphosis-dev
 //
 // This program is free software: you can redistribute it and/or modify
@@ -27,7 +27,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 type YouTubeEngine struct {