P1.1: Registry package with full CRUD and tests

SQLite schema (services, components, ports, volumes, cmd, events),
migrations, and complete CRUD operations. 7 tests covering:
idempotent migration, service CRUD, duplicate name rejection,
component CRUD with ports/volumes/cmd, composite PK enforcement,
cascade delete, and event insert/query/count/prune.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

internal/registry/services.go

@@ -0,0 +1,94 @@
+package registry
+
+import (
+	"database/sql"
+	"fmt"
+	"time"
+)
+
+// Service represents a service in the registry.
+type Service struct {
+	Name      string
+	Active    bool
+	CreatedAt time.Time
+	UpdatedAt time.Time
+}
+
+// CreateService creates a new service in the registry.
+func CreateService(db *sql.DB, name string, active bool) error {
+	_, err := db.Exec(
+		"INSERT INTO services (name, active) VALUES (?, ?)",
+		name, active,
+	)
+	if err != nil {
+		return fmt.Errorf("create service %q: %w", name, err)
+	}
+	return nil
+}
+
+// GetService retrieves a service by name.
+func GetService(db *sql.DB, name string) (*Service, error) {
+	s := &Service{}
+	var createdAt, updatedAt string
+	err := db.QueryRow(
+		"SELECT name, active, created_at, updated_at FROM services WHERE name = ?",
+		name,
+	).Scan(&s.Name, &s.Active, &createdAt, &updatedAt)
+	if err != nil {
+		return nil, fmt.Errorf("get service %q: %w", name, err)
+	}
+	s.CreatedAt, _ = time.Parse("2006-01-02 15:04:05", createdAt)
+	s.UpdatedAt, _ = time.Parse("2006-01-02 15:04:05", updatedAt)
+	return s, nil
+}
+
+// ListServices returns all services.
+func ListServices(db *sql.DB) ([]Service, error) {
+	rows, err := db.Query("SELECT name, active, created_at, updated_at FROM services ORDER BY name")
+	if err != nil {
+		return nil, fmt.Errorf("list services: %w", err)
+	}
+	defer func() { _ = rows.Close() }()
+
+	var services []Service
+	for rows.Next() {
+		var s Service
+		var createdAt, updatedAt string
+		if err := rows.Scan(&s.Name, &s.Active, &createdAt, &updatedAt); err != nil {
+			return nil, fmt.Errorf("scan service: %w", err)
+		}
+		s.CreatedAt, _ = time.Parse("2006-01-02 15:04:05", createdAt)
+		s.UpdatedAt, _ = time.Parse("2006-01-02 15:04:05", updatedAt)
+		services = append(services, s)
+	}
+	return services, rows.Err()
+}
+
+// UpdateServiceActive updates a service's active flag.
+func UpdateServiceActive(db *sql.DB, name string, active bool) error {
+	res, err := db.Exec(
+		"UPDATE services SET active = ?, updated_at = datetime('now') WHERE name = ?",
+		active, name,
+	)
+	if err != nil {
+		return fmt.Errorf("update service %q: %w", name, err)
+	}
+	n, _ := res.RowsAffected()
+	if n == 0 {
+		return fmt.Errorf("update service %q: %w", name, sql.ErrNoRows)
+	}
+	return nil
+}
+
+// DeleteService removes a service and all its components (via CASCADE).
+func DeleteService(db *sql.DB, name string) error {
+	res, err := db.Exec("DELETE FROM services WHERE name = ?", name)
+	if err != nil {
+		return fmt.Errorf("delete service %q: %w", name, err)
+	}
+	n, _ := res.RowsAffected()
+	if n == 0 {
+		return fmt.Errorf("delete service %q: %w", name, sql.ErrNoRows)
+	}
+	return nil
+}