Add Arrtrix runtime, config, onboarding, and webhook support

- Implement runtime package for bridge startup, config loading, and env
  overrides
- Add onboarding package for management room welcome messages
- Add matrixcmd package for command processing and help
- Add webhook package with Radarr webhook support and validation
- Extend connector config for webhooks and validation
- Update default config and example config for new options
- Add tests for new packages and config validation
- Change database type default to sqlite3-fk-wal

packages/arrtrix/pkg/runtime/main_test.go

@@ -0,0 +1,30 @@
+package runtime
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"maunium.net/go/mautrix/bridgev2/bridgeconfig"
+)
+
+func TestLoadRegistrationTokens(t *testing.T) {
+	tempDir := t.TempDir()
+	registrationPath := filepath.Join(tempDir, "registration.yaml")
+	if err := os.WriteFile(registrationPath, []byte("as_token: app-token\nhs_token: hs-token\n"), 0o600); err != nil {
+		t.Fatalf("failed to write registration file: %v", err)
+	}
+
+	cfg := &bridgeconfig.Config{}
+	main := &Main{RegistrationPath: registrationPath}
+	if err := main.loadRegistrationTokens(cfg); err != nil {
+		t.Fatalf("loadRegistrationTokens returned error: %v", err)
+	}
+
+	if cfg.AppService.ASToken != "app-token" {
+		t.Fatalf("expected as token to be loaded, got %q", cfg.AppService.ASToken)
+	}
+	if cfg.AppService.HSToken != "hs-token" {
+		t.Fatalf("expected hs token to be loaded, got %q", cfg.AppService.HSToken)
+	}
+}