fix(prefs): persist favicon choice and apply to HTML results

- Save favicon cookie on POST /preferences; reflect selection in template
- Add getFaviconService helper; pass favicon service into FromResponse
- Compute ResultView.FaviconIconURL (none/google/duckduckgo/self proxy)
- Update result_item and video_item templates; add httpapi/views tests

Made-with: Cursor

internal/views/views_test.go

@@ -1,6 +1,7 @@
 package views
 
 import (
+	"strings"
 	"testing"
 
 	"github.com/metamorphosis-dev/samsa/internal/contracts"
@@ -37,7 +38,7 @@ func mockEmptyResponse() contracts.SearchResponse {
 
 func TestFromResponse_Basic(t *testing.T) {
 	resp := mockSearchResponse("samsa trial", 42)
-	data := FromResponse(resp, "samsa trial", 1, "", "", "")
+	data := FromResponse(resp, "samsa trial", 1, "", "", "", "none")
 
 	if data.Query != "samsa trial" {
 		t.Errorf("expected query 'samsa trial', got %q", data.Query)
@@ -55,7 +56,7 @@ func TestFromResponse_Basic(t *testing.T) {
 
 func TestFromResponse_Pagination(t *testing.T) {
 	resp := mockSearchResponse("test", 100)
-	data := FromResponse(resp, "test", 3, "", "", "")
+	data := FromResponse(resp, "test", 3, "", "", "", "none")
 
 	if data.PrevPage != 2 {
 		t.Errorf("expected PrevPage 2, got %d", data.PrevPage)
@@ -80,7 +81,7 @@ func TestFromResponse_Pagination(t *testing.T) {
 }
 
 func TestFromResponse_Empty(t *testing.T) {
-	data := FromResponse(mockEmptyResponse(), "", 1, "", "", "")
+	data := FromResponse(mockEmptyResponse(), "", 1, "", "", "", "none")
 
 	if data.NumberOfResults != 0 {
 		t.Errorf("expected 0 results, got %d", data.NumberOfResults)
@@ -90,6 +91,31 @@ func TestFromResponse_Empty(t *testing.T) {
 	}
 }
 
+func TestFromResponse_FaviconIconURL(t *testing.T) {
+	u := "https://example.com/path"
+	resp := contracts.SearchResponse{
+		Query:               "q",
+		NumberOfResults:     1,
+		Results:             []contracts.MainResult{{Title: "t", URL: &u, Engine: "bing"}},
+		Answers:             []map[string]any{},
+		Corrections:         []string{},
+		Infoboxes:           []map[string]any{},
+		Suggestions:         []string{},
+		UnresponsiveEngines:   [][2]string{},
+	}
+	data := FromResponse(resp, "q", 1, "", "", "", "google")
+	if len(data.Results) != 1 {
+		t.Fatalf("expected 1 result, got %d", len(data.Results))
+	}
+	got := data.Results[0].FaviconIconURL
+	if got == "" || !strings.Contains(got, "google.com/s2/favicons") {
+		t.Fatalf("expected google favicon URL, got %q", got)
+	}
+	if !strings.Contains(got, "example.com") {
+		t.Fatalf("expected domain in favicon URL, got %q", got)
+	}
+}
+
 func TestIsHTMXRequest(t *testing.T) {
 	tests := []struct {
 		name    string