refactor: convert frontend from submodule to true monorepo

Convert frontend from Git submodule to a regular monorepo directory for simplified development workflow.

Changes:
- Remove frontend submodule tracking (mode 160000 gitlink)
- Add all frontend source files directly to main repository
- Remove frontend/.git directory
- Update CLAUDE.md to clarify true monorepo structure
- Update Frontend Architecture documentation (React Router v6, Socket.IO, Leaflet, ErrorBoundary)

Benefits of Monorepo:
- Single git clone for entire project
- Unified commit history
- Simpler CI/CD pipeline
- Easier for new developers
- No submodule sync issues
- Atomic commits across frontend and backend

Frontend Files Added:
- All React components (MapView, ErrorBoundary, TaskList, SocialFeed, etc.)
- Context providers (AuthContext, SocketContext)
- Complete test suite with MSW
- Dependencies and configuration files

Branch Cleanup:
- Using 'main' as default branch (develop deleted)
- Frontend no longer has separate Git history

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

frontend/src/components/Navbar.js

@@ -0,0 +1,60 @@
+import React, { useContext } from 'react';
+import { Link } from 'react-router-dom';
+import { AuthContext } from '../context/AuthContext';
+
+const Navbar = () => {
+  const { auth, logout } = useContext(AuthContext);
+
+  const authLinks = (
+    <ul className="navbar-nav ml-auto">
+      <li className="nav-item">
+        <Link className="nav-link" to="/map">Map</Link>
+      </li>
+      <li className="nav-item">
+        <Link className="nav-link" to="/tasks">Tasks</Link>
+      </li>
+      <li className="nav-item">
+        <Link className="nav-link" to="/feed">Feed</Link>
+      </li>
+      <li className="nav-item">
+        <Link className="nav-link" to="/events">Events</Link>
+      </li>
+      <li className="nav-item">
+        <Link className="nav-link" to="/rewards">Rewards</Link>
+      </li>
+      <li className="nav-item">
+        <Link className="nav-link" to="/profile">Profile</Link>
+      </li>
+      <li className="nav-item">
+        <Link className="nav-link" to="/premium">Premium</Link>
+      </li>
+      <li className="nav-item">
+        <a onClick={logout} href="#!" className="nav-link">Logout</a>
+      </li>
+    </ul>
+  );
+
+  const guestLinks = (
+    <ul className="navbar-nav ml-auto">
+      <li className="nav-item">
+        <Link className="nav-link" to="/register">Register</Link>
+      </li>
+      <li className="nav-item">
+        <Link className="nav-link" to="/login">Login</Link>
+      </li>
+    </ul>
+  );
+
+  return (
+    <nav className="navbar navbar-expand-sm navbar-dark bg-dark mb-4">
+      <div className="container">
+        <Link className="navbar-brand" to="/">Adopt-a-Street</Link>
+        <div className="collapse navbar-collapse">
+          {auth.isAuthenticated ? authLinks : guestLinks}
+        </div>
+      </div>
+    </nav>
+  );
+};
+
+export default Navbar;