Consolidate backend: drop vendored APwhy, converge on goose + sqlc

Phase 0 cleanup verified end-to-end:

- Delete vendored APwhy runtime (cmd/apwhy, internal/apwhy) and the
  unwired copy (internal/api/server.go + static bundle + cloned
  internal/{storage,analytics,auth,rbac}) — ~7.5k lines of dead code.
- Keep Containr's native internal/gateway; move APwhy management
  routes under /api/v1/gateway/* so they stop colliding with the
  native /services paths. Fix handlers against the real schema:
  UUID ids via RETURNING, integer enabled flags, plan validation,
  service validate endpoint, unique-violation mapping.
- Port agents.go off GORM onto sqlc (sqlc/queries/agents.sql);
  drop gorm dependencies; fix sqlc schema drift (services.environment_id).
- Replace the SELECT 1 goose baseline with the real consolidated
  schema (52 tables) minus APwhy's parallel auth/RBAC objects;
  idempotent via IF NOT EXISTS / OR REPLACE / guarded DO blocks so it
  replays cleanly over legacy installs. Add a drop migration for the
  dead objects and delete the legacy filename-tracked migrations/
  loader, directory, and Dockerfile copy. Verified via cmd/migrate:
  fresh install 53 tables, legacy upgrade clean to 20260917000000.
- Canvas: add invisible React Flow handles to ServiceNode so inferred
  auto-connections stop emitting warning #008.
- Remove reactflow dep (superseded by @xyflow/react), test harness
  cmds, and legacy 0001_init.sql backups.

Authored By: TDvorak <[email protected]>

app/backend/cmd/migrate/main.go

@@ -25,11 +25,6 @@ func main() {
 	}
 	defer db.Close()
 
-	legacyDir := os.Getenv("LEGACY_MIGRATIONS_DIR")
-	if legacyDir == "" {
-		legacyDir = "migrations"
-	}
-
 	gooseDir := os.Getenv("GOOSE_MIGRATIONS_DIR")
 	if gooseDir == "" {
 		gooseDir = "migrations_goose"
@@ -41,24 +36,14 @@ func main() {
 	}
 
 	switch command {
-	case "up":
+	case "up", "goose-up":
 		migrationCtx, migrationCancel := context.WithTimeout(context.Background(), cfg.MigrationLockTimeout)
-		if err := db.MigrateAllWithLock(migrationCtx, legacyDir, gooseDir); err != nil {
+		if err := db.MigrateAllWithLock(migrationCtx, gooseDir); err != nil {
 			migrationCancel()
 			log.Fatalf("Migration failed: %v", err)
 		}
 		migrationCancel()
-		log.Println("Legacy + goose migrations completed successfully")
-	case "legacy-up":
-		if err := db.Migrate(legacyDir); err != nil {
-			log.Fatalf("Legacy migration failed: %v", err)
-		}
-		log.Println("Legacy migrations completed successfully")
-	case "goose-up":
-		if err := db.MigrateGoose(gooseDir); err != nil {
-			log.Fatalf("Goose migration failed: %v", err)
-		}
-		log.Println("Goose migrations completed successfully")
+		log.Println("Migrations completed successfully")
 	case "goose-status":
 		if err := db.GooseStatus(gooseDir); err != nil {
 			log.Fatalf("Goose status failed: %v", err)
@@ -73,6 +58,6 @@ func main() {
 		}
 		log.Printf("Created goose migration %q in %q", name, gooseDir)
 	default:
-		log.Fatalf("Unknown command %q. Supported commands: up | legacy-up | goose-up | goose-status | goose-create", command)
+		log.Fatalf("Unknown command %q. Supported commands: up | goose-status | goose-create", command)
 	}
 }