feat(search): personalize suggestions by listening history (M6)

Suggest fetches three times as many candidates and reranks them in the API:
what the user plays, finishes and likes moves up a few positions and what they
dislike moves down, with Meilisearch relevance still the base order.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

services/api/internal/search/translit_test.go

@@ -3,6 +3,8 @@ package search
 import (
 	"testing"
 
+	"github.com/google/uuid"
+
 	"github.com/stretchr/testify/assert"
 )
 
@@ -20,3 +22,14 @@ func TestSwitchLayout(t *testing.T) {
 	assert.Equal(t, "кино", SwitchLayout("rbyj"))
 	assert.Equal(t, "", SwitchLayout("123"))
 }
+
+func TestPersonalizeLiftsFamiliarAndSinksDisliked(t *testing.T) {
+	liked, disliked := uuid.New(), uuid.New()
+	other := []string{uuid.NewString(), uuid.NewString(), uuid.NewString()}
+	found := []string{other[0], disliked.String(), other[1], other[2], liked.String()}
+	aff := map[uuid.UUID]float64{liked: 30, disliked: -10}
+
+	got := personalize(found, aff, 3)
+	assert.Equal(t, []string{liked.String(), other[0], other[1]}, got)
+	assert.Equal(t, found[:2], personalize(found, nil, 2), "без вкуса — порядок релевантности")
+}