Auth flow refactor, project requests, and routing updates

- Add server-side auth token loader (auth.server.ts) with SSR cookie forwarding
- Add project-requests client for explicit/signal/existing issue dispatch
- Refactor auth layout and app layout for SSR auth gating
- Update auth-client and auth-provider for convex token flow
- Extend project-issue primitives with request result schema
- Wire projectIssues backend mutation for request handling
- Update slice-one page and project-workspace hook
- Adjust routes (remove unused), Caddy config, and env templates

.env.example

@@ -6,8 +6,8 @@ SITE_URL=http://localhost:5173
 NATIVE_APP_URL=code://
 
 # Browser and native public endpoints
+VITE_AUTH_URL=http://localhost:5173
 VITE_CONVEX_URL=https://example.convex.cloud
-VITE_CONVEX_SITE_URL=https://example.convex.site
 # For phone testing, replace localhost with this machine's Tailscale IPv4 address.
 VITE_FLUE_URL=http://localhost:3583
 EXPO_PUBLIC_CONVEX_URL=https://example.convex.cloud