feat: project detail overhaul, realtime updates, avatar RLS fix

- ProjectDetail: full redesign — icon meta row, completion progress bar, main contact card, activity feed, subcontractor management modal with multi-select
- ProjectDetail: task table matches Tasks.jsx (R#, assigned avatar, priority, type, deadline, status) with status tabs + counts
- Realtime: useRefetchOnFocus + useRealtimeSubscription hooks wired to Tasks, TaskDetail, ProjectDetail, TeamDashboard
- AuthContext: live profile updates via Supabase realtime channel
- Tasks/ProjectDetail: assignee avatar join added for all roles (client, external, team)
- RLS: allow all authenticated users to read profiles (fixes avatar display across roles)
- RequestForm: lockedFields prop for pre-filled read-only company/project fields

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

src/hooks/useRealtimeSubscription.js

@@ -0,0 +1,17 @@
+import { useEffect, useRef } from 'react';
+import { supabase } from '../lib/supabase';
+
+export function useRealtimeSubscription(tables, onchange) {
+  const onchangeRef = useRef(onchange);
+  useEffect(() => { onchangeRef.current = onchange; });
+
+  useEffect(() => {
+    const channelName = `rt-${tables.join('-')}-${Date.now()}`;
+    let channel = supabase.channel(channelName);
+    for (const table of tables) {
+      channel = channel.on('postgres_changes', { event: '*', schema: 'public', table }, () => onchangeRef.current());
+    }
+    channel.subscribe();
+    return () => { supabase.removeChannel(channel); };
+  }, []); // eslint-disable-line react-hooks/exhaustive-deps
+}

src/hooks/useRefetchOnFocus.js

@@ -0,0 +1,12 @@
+import { useEffect, useRef } from 'react';
+
+export function useRefetchOnFocus(refetch) {
+  const refetchRef = useRef(refetch);
+  useEffect(() => { refetchRef.current = refetch; });
+
+  useEffect(() => {
+    const onFocus = () => refetchRef.current();
+    window.addEventListener('focus', onFocus);
+    return () => window.removeEventListener('focus', onFocus);
+  }, []);
+}