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/cache/cache_test.go

@@ -3,13 +3,13 @@ package cache
 import (
 	"testing"
 
-	"github.com/metamorphosis-dev/kafka/internal/contracts"
+	"github.com/metamorphosis-dev/samsa/internal/contracts"
 )
 
 func TestKey_Deterministic(t *testing.T) {
 	req := contracts.SearchRequest{
 		Format:     contracts.FormatJSON,
-		Query:      "kafka metamorphosis",
+		Query:      "samsa metamorphosis",
 		Pageno:     1,
 		Safesearch: 0,
 		Language:   "auto",
@@ -29,7 +29,7 @@ func TestKey_Deterministic(t *testing.T) {
 }
 
 func TestKey_DifferentQueries(t *testing.T) {
-	reqA := contracts.SearchRequest{Query: "kafka", Format: contracts.FormatJSON}
+	reqA := contracts.SearchRequest{Query: "samsa", Format: contracts.FormatJSON}
 	reqB := contracts.SearchRequest{Query: "orwell", Format: contracts.FormatJSON}
 
 	if Key(reqA) == Key(reqB) {