feat(03-01): add shared postgres pool and plugin migrations

Open one pgx stdlib *sql.DB, hand it to GORM, and run per-plugin
gormigrate sets with isolated history tables after an ICU pl-PL check.

Co-authored-by: Cursor <cursoragent@cursor.com>

internal/build/build.go

@@ -85,6 +85,7 @@ func generateMain(m Manifest) ([]byte, error) {
 	b.WriteString("\t\"git.golem15.com/golem15/summercms/backpack\"\n")
 	b.WriteString("\t\"git.golem15.com/golem15/summercms/bonfire\"\n")
 	b.WriteString("\t\"git.golem15.com/golem15/summercms/compass\"\n")
+	b.WriteString("\t\"git.golem15.com/golem15/summercms/lagoon\"\n")
 	b.WriteString("\t\"git.golem15.com/golem15/summercms/pact\"\n")
 	b.WriteString("\t\"git.golem15.com/golem15/summercms/party\"\n")
 	b.WriteString(")\n\n")
@@ -104,7 +105,7 @@ func generateMain(m Manifest) ([]byte, error) {
 	b.WriteString("\tif err != nil {\n")
 	b.WriteString("\t\treturn err\n")
 	b.WriteString("\t}\n")
-	b.WriteString("\tvar commands []bonfire.Command\n")
+	b.WriteString("\tcommands := lagoon.RuntimeCommands(app, plugins)\n")
 	b.WriteString("\tfor _, plugin := range plugins {\n")
 	b.WriteString("\t\tif hasCommands, ok := plugin.(pact.HasCommands); ok {\n")
 	b.WriteString("\t\t\tcommands = append(commands, hasCommands.Commands()...)\n")

internal/build/build_test.go

@@ -94,6 +94,9 @@ func TestGenerateStableQuotedImportsInManifestOrder(t *testing.T) {
 	if !bytes.Contains(mainSrc, []byte(`bonfire.NewRoot("hello"`)) {
 		t.Fatalf("main does not use manifest binary:\n%s", mainSrc)
 	}
+	if !bytes.Contains(mainSrc, []byte("lagoon.RuntimeCommands")) {
+		t.Fatalf("main does not register lagoon runtime commands:\n%s", mainSrc)
+	}
 	if bytes.Contains(mainSrc, []byte("examples/hello")) {
 		t.Fatal("generated main hard-codes examples/hello")
 	}

internal/build/manifest.go

@@ -121,6 +121,11 @@ func ValidatePluginID(id string) error {
 	return nil
 }
 
+// FindAppDir walks up from start looking for summer.yaml.
+func FindAppDir(start string) (string, error) {
+	return findAppDir(start)
+}
+
 func findAppDir(start string) (string, error) {
 	if start == "" {
 		return "", fmt.Errorf("build: app directory is empty")