feat: skeleton loaders, Sentry source maps, auto-deploy via webhook

RoomSkeleton: shimmer skeleton matching Room header/timeline/input layout,
  used as Suspense fallback for all three Room routes (home/direct/space)

Sentry source maps: @sentry/vite-plugin uploads 72 hidden source map files
  to Sentry on each build then deletes them from dist — stack traces now show
  real file/line numbers instead of minified bundle positions.
  Auth token loaded from /etc/lotus-deploy.env (not in git).

Auto-deploy: webhook receiver on port 9001, nginx proxies
  /hooks/lotus-deploy, HMAC-SHA256 verified, triggers on lotus branch push.
  Deploy script: git reset --hard + npm ci + npm run build + rsync to webroot.

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

vite.config.js

@@ -1,5 +1,6 @@
 import { defineConfig } from 'vite';
 import react from '@vitejs/plugin-react';
+import { sentryVitePlugin } from '@sentry/vite-plugin';
 import { wasm } from '@rollup/plugin-wasm';
 import { viteStaticCopy } from 'vite-plugin-static-copy';
 import { vanillaExtractPlugin } from '@vanilla-extract/vite-plugin';
@@ -94,6 +95,17 @@ export default defineConfig({
     vanillaExtractPlugin(),
     wasm(),
     react(),
+    // Upload source maps to Sentry when auth token is present, then delete maps from dist
+    ...(process.env.SENTRY_AUTH_TOKEN ? [sentryVitePlugin({
+      org: 'lotus-guild',
+      project: 'javascript-react',
+      authToken: process.env.SENTRY_AUTH_TOKEN,
+      sourcemaps: {
+        filesToDeleteAfterUpload: ['./dist/**/*.map'],
+      },
+      release: { name: process.env.VITE_APP_VERSION ?? 'lotus' },
+      telemetry: false,
+    })] : []),
     VitePWA({
       srcDir: 'src',
       filename: 'sw.ts',
@@ -125,7 +137,7 @@ export default defineConfig({
   },
   build: {
     outDir: 'dist',
-    sourcemap: false,
+    sourcemap: process.env.SENTRY_AUTH_TOKEN ? 'hidden' : false,
     copyPublicDir: false,
     rollupOptions: {
       plugins: [inject({ Buffer: ['buffer', 'Buffer'] })],