Implement Issue #1: User Accounts & Profiles

- Admin-only account creation (no self-registration); invite-token flow
  replaces the public /auth/register endpoint
- New volunteer fields: phone, is_trainee, operational_roles,
  notification_preference, admin_notes, last_login, completed_shifts
- Role-scoped profile editing: volunteers update name/phone only;
  admins update all fields including notes and trainee flag
- /auth/activate endpoint for invite-token-based account activation
- /api/v1/volunteers/{id}/invite for admin to resend invite links
- last_login recorded on each successful authentication

Tests:
- Go: handler tests (auth rules, create, activate, update scoping) via
  Storer/AuthServicer interfaces and fake store; auth unit tests for
  HashPassword, IssueToken, and Parse
- Frontend: RTL tests for Activate, Profile, and Volunteers pages
- Fixed CRA 5 + React Router v7 Jest compatibility (moduleNameMapper +
  TextEncoder polyfill)
- Replaced stale CRA App.test.tsx placeholder with real tests

CI:
- .gitea/workflows/ci.yml runs go vet, go test, tsc, and npm test on
  every push and pull request

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/server/server.go

@@ -42,17 +42,19 @@ func New(db *sql.DB, jwtSecret string, staticDir string) http.Handler {
 	// API routes
 	r.Route("/api/v1", func(r chi.Router) {
 		// Public auth endpoints
-		r.Post("/auth/register", volunteerHandler.Register)
 		r.Post("/auth/login", volunteerHandler.Login)
+		r.Post("/auth/activate", volunteerHandler.Activate)
 
 		// Protected routes
 		r.Group(func(r chi.Router) {
 			r.Use(middleware.Authenticate(authSvc))
 
 			// Volunteers
+			r.With(middleware.RequireAdmin).Post("/volunteers", volunteerHandler.Create)
 			r.Get("/volunteers", volunteerHandler.List)
 			r.Get("/volunteers/{id}", volunteerHandler.Get)
-			r.With(middleware.RequireAdmin).Put("/volunteers/{id}", volunteerHandler.Update)
+			r.Put("/volunteers/{id}", volunteerHandler.Update)
+			r.With(middleware.RequireAdmin).Post("/volunteers/{id}/invite", volunteerHandler.ResendInvite)
 
 			// Schedules
 			r.Get("/schedules", scheduleHandler.List)