feat: fuzzy search with parallel DB/MusicBrainz execution

- Add pg_trgm fuzzy search to PostgreSQL artist repository
- Add Lucene fuzzy query (~0.7) for MusicBrainz artist search
- Run DB and MusicBrainz searches in parallel goroutines
- Cache MusicBrainz results to DB for accumulation
- Deduplicate results by external ID
- Filter out special purpose artists (type=Other)
- Add SaveAll method for batch artist inserts
- Move database schema to containers repo

internal/provider/musicbrainz/provider.go

@@ -42,8 +42,8 @@ func (p *Provider) SearchArtists(ctx context.Context, query string, limit, offse
 		limit = 25
 	}
 
-	escapedQuery := escapeQuery(query)
-	data, err := p.client.search(ctx, "artist", fmt.Sprintf("artist:%s", escapedQuery), limit, offset)
+	luceneQuery := buildFuzzyArtistQuery(query, 0.7)
+	data, err := p.client.search(ctx, "artist", luceneQuery, limit, offset)
 	if err != nil {
 		return nil, fmt.Errorf("search artists: %w", err)
 	}
@@ -311,6 +311,31 @@ func selectCanonicalRelease(releases []*mbRelease) *mbRelease {
 	return best
 }
 
+func buildFuzzyArtistQuery(query string, similarity float64) string {
+	terms := strings.Fields(query)
+	if len(terms) == 0 {
+		return ""
+	}
+
+	var parts []string
+	for _, term := range terms {
+		escaped := escapeForFuzzy(term)
+		parts = append(parts, fmt.Sprintf("%s~%.1f", escaped, similarity))
+	}
+
+	termQuery := strings.Join(parts, " AND ")
+	return fmt.Sprintf("(artist:(%s) OR alias:(%s))", termQuery, termQuery)
+}
+
+func escapeForFuzzy(s string) string {
+	special := []string{`+`, `-`, `&`, `|`, `!`, `(`, `)`, `{`, `}`, `[`, `]`, `^`, `"`, `:`, `/`, `\`}
+	result := s
+	for _, char := range special {
+		result = strings.ReplaceAll(result, char, `\`+char)
+	}
+	return result
+}
+
 func escapeQuery(s string) string {
 	special := []string{`+`, `-`, `&`, `|`, `!`, `(`, `)`, `{`, `}`, `[`, `]`, `^`, `"`, `~`, `*`, `?`, `:`, `/`, `\`}
 	result := s