feat: fruit search by name/synonym and type filter (story #06)

Backend: List repo query gains name (ILIKE with wildcard escaping on
name + synonym LEFT JOIN, SELECT DISTINCT) and types (ANY cast) params;
handler parses ?name= and ?type=, resolves combined-type aliases from
domain.FruitTypeAliases, validates plain types against validFruitTypes
to prevent Postgres enum cast errors. ORDER BY f.name, f.id for stable
pagination.

Frontend: listFruits gains optional {name, type} params; fruitStore adds
searchName/searchType state and setSearch action (resets offset, refetches);
FruitList.vue wires text input (debounced 300 ms + Enter) and flat type
dropdown (17 enum values + 4 aliases per spec §5 order); debounce timer
cleared on unmount.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

backend/internal/repository/fruit_repo.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"strings"
 
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgconn"
@@ -33,15 +34,35 @@ func mapPgError(err error) error {
 	return err
 }
 
-func (r *FruitRepo) List(ctx context.Context, limit, offset int) ([]domain.Fruit, int, error) {
+func escapeLike(s string) string {
+	s = strings.ReplaceAll(s, `\`, `\\`)
+	s = strings.ReplaceAll(s, `%`, `\%`)
+	s = strings.ReplaceAll(s, `_`, `\_`)
+	return s
+}
+
+func (r *FruitRepo) List(ctx context.Context, limit, offset int, name string, types []string) ([]domain.Fruit, int, error) {
+	escaped := escapeLike(name)
+	countRow := r.pool.QueryRow(ctx,
+		`SELECT COUNT(DISTINCT f.id)
+		 FROM fruits f
+		 LEFT JOIN fruit_synonyms fs ON fs.fruit_id = f.id
+		 WHERE ($1 = '' OR f.name ILIKE '%' || $1 || '%' ESCAPE '\' OR fs.synonym ILIKE '%' || $1 || '%' ESCAPE '\')
+		   AND ($2::fruit_type[] IS NULL OR f.fruit_type = ANY($2::fruit_type[]))`,
+		escaped, types)
 	var total int
-	if err := r.pool.QueryRow(ctx, "SELECT COUNT(*) FROM fruits").Scan(&total); err != nil {
+	if err := countRow.Scan(&total); err != nil {
 		return nil, 0, err
 	}
 
 	rows, err := r.pool.Query(ctx,
-		`SELECT id, name, osdb_number, comment, fruit_type, created_at, updated_at
-		 FROM fruits ORDER BY id LIMIT $1 OFFSET $2`, limit, offset)
+		`SELECT DISTINCT f.id, f.name, f.osdb_number, f.comment, f.fruit_type, f.created_at, f.updated_at
+		 FROM fruits f
+		 LEFT JOIN fruit_synonyms fs ON fs.fruit_id = f.id
+		 WHERE ($1 = '' OR f.name ILIKE '%' || $1 || '%' ESCAPE '\' OR fs.synonym ILIKE '%' || $1 || '%' ESCAPE '\')
+		   AND ($2::fruit_type[] IS NULL OR f.fruit_type = ANY($2::fruit_type[]))
+		 ORDER BY f.name, f.id LIMIT $3 OFFSET $4`,
+		escaped, types, limit, offset)
 	if err != nil {
 		return nil, 0, err
 	}

backend/internal/repository/fruit_repo_integration_test.go

@@ -97,7 +97,7 @@ func TestFruitRepoIntegration(t *testing.T) {
 	}
 
 	// List
-	fruits, total, err := repo.List(ctx, 50, 0)
+	fruits, total, err := repo.List(ctx, 50, 0, "", nil)
 	if err != nil {
 		t.Fatalf("List: %v", err)
 	}