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>

cmd/summer/runtime.go

@@ -0,0 +1,96 @@
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+
+	"git.golem15.com/golem15/summercms/bonfire"
+	"git.golem15.com/golem15/summercms/internal/build"
+)
+
+func delegateCommand(name, description string) bonfire.Command {
+	return bonfire.Command{
+		Name:        name,
+		Description: description,
+		Run: func(ctx context.Context, in bonfire.Input, out bonfire.Output) error {
+			argv := []string{name}
+			argv = append(argv, in.Args()...)
+			return runAppBinary(ctx, argv, out)
+		},
+	}
+}
+
+func delegateRollbackCommand() bonfire.Command {
+	return bonfire.Command{
+		Name:        "migrate:rollback",
+		Description: "Roll back the last migration of a plugin in the app binary",
+		Flags: []bonfire.Flag{{
+			Name:        "plugin",
+			Description: "Plugin ID whose last migration to roll back",
+		}},
+		Run: func(ctx context.Context, in bonfire.Input, out bonfire.Output) error {
+			argv := []string{"migrate:rollback"}
+			if plugin, ok := in.Flag("plugin"); ok && plugin != "" {
+				argv = append(argv, "--plugin", plugin)
+			}
+			argv = append(argv, in.Args()...)
+			return runAppBinary(ctx, argv, out)
+		},
+	}
+}
+
+func runAppBinary(ctx context.Context, argv []string, out bonfire.Output) error {
+	if len(argv) == 0 {
+		return fmt.Errorf("summer: missing app command")
+	}
+	dir, err := os.Getwd()
+	if err != nil {
+		return err
+	}
+	appDir, err := build.FindAppDir(dir)
+	if err != nil {
+		return err
+	}
+	m, err := build.LoadManifest(filepath.Join(appDir, "summer.yaml"))
+	if err != nil {
+		return err
+	}
+	bin := filepath.Join(appDir, "bin", m.Binary)
+	if _, err := os.Stat(bin); err != nil {
+		if err := build.App(ctx, appDir, out); err != nil {
+			return err
+		}
+	}
+	self, err := os.Executable()
+	if err == nil {
+		if same, _ := sameFile(self, bin); same {
+			return fmt.Errorf("summer: refusing to recurse into %s", bin)
+		}
+	}
+	cmd := exec.CommandContext(ctx, bin, argv...)
+	cmd.Dir = appDir
+	cmd.Stdout = out
+	cmd.Stderr = out
+	cmd.Stdin = os.Stdin
+	cmd.Env = os.Environ()
+	if err := cmd.Run(); err != nil {
+		return fmt.Errorf("summer: %s: %w", strings.Join(argv, " "), err)
+	}
+	return nil
+}
+
+func sameFile(a, b string) (bool, error) {
+	ai, err := os.Stat(a)
+	if err != nil {
+		return false, err
+	}
+	bi, err := os.Stat(b)
+	if err != nil {
+		return false, err
+	}
+	return os.SameFile(ai, bi), nil
+}