chore: initial commit — UdyamLinc UI, phases A-E

Vite/React 19 console and enterprise PWA. Officer console screens, offline
ledger and sync, data feeds and trip-wire rules screens with freshness chip.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

public/sw.js

@@ -0,0 +1,54 @@
+/*
+ * UdyamLinc service worker — app-shell precache + stale-while-revalidate.
+ *
+ * Scope of the offline promise (deck feature 7): the enterprise PWA must open,
+ * render and accept ledger entries with zero connectivity. Ledger writes are
+ * queued in localStorage by the app itself (see lib/ledgerStore.ts); this worker
+ * only guarantees the shell and its assets are reachable.
+ */
+const CACHE = 'udyamlinc-v1'
+const SHELL = ['/', '/app', '/index.html', '/manifest.webmanifest', '/udyamlinc-tile.svg']
+
+self.addEventListener('install', (event) => {
+  event.waitUntil(caches.open(CACHE).then((c) => c.addAll(SHELL)).then(() => self.skipWaiting()))
+})
+
+self.addEventListener('activate', (event) => {
+  event.waitUntil(
+    caches
+      .keys()
+      .then((keys) => Promise.all(keys.filter((k) => k !== CACHE).map((k) => caches.delete(k))))
+      .then(() => self.clients.claim()),
+  )
+})
+
+self.addEventListener('fetch', (event) => {
+  const req = event.request
+  if (req.method !== 'GET') return
+
+  const url = new URL(req.url)
+  // API calls are never served stale — the app falls back to its local store instead.
+  if (url.pathname.includes('/api/')) return
+
+  // Navigations: network first, fall back to the cached shell when offline.
+  if (req.mode === 'navigate') {
+    event.respondWith(fetch(req).catch(() => caches.match('/index.html')))
+    return
+  }
+
+  // Assets: cache first, refresh in the background.
+  event.respondWith(
+    caches.match(req).then((hit) => {
+      const network = fetch(req)
+        .then((res) => {
+          if (res.ok) {
+            const copy = res.clone()
+            caches.open(CACHE).then((c) => c.put(req, copy))
+          }
+          return res
+        })
+        .catch(() => hit)
+      return hit || network
+    }),
+  )
+})