Add Web Push, guided start screen, SVG icons, chunked uploads, rename

- Web Push (VAPID + RFC 8291, pure Rust): permission/question/finished
  notifications while no app window is visible; settings with test button
- Guided new-session flow: task, craft target (website/app/game/old
  software/fresh), clean room or deep, description, model, folder
  (new, existing or cloned git repository); originals upload to original/
- Craft phase bar (craft_phase tool) for study/specify/build/check/ready
- Chunked uploads (8 MB) up to server.max_upload_mb (default 500 MB)
- All UI glyphs and emojis replaced by themeable SVG icons
- Rename dialog with manual name or model-generated suggestion

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

server/src/main.rs

@@ -16,6 +16,7 @@ mod mentions;
 mod mcp;
 mod permission;
 mod prompts;
+mod push;
 mod provider;
 mod reverse;
 mod runner;
@@ -47,6 +48,7 @@ async fn main() -> Result<()> {
     let bind = cfg.server.bind.clone();
     let app = app::App::new(path, cfg).await?;
     lsp::spawn_reaper(app.clone());
+    push::spawn_listener(app.clone());
     let router = api::router(app);
     let listener = tokio::net::TcpListener::bind(&bind).await?;
     tracing::info!("listening on http://{bind}");