refactor: rename files to PascalCase components and kebab-case APIs (Task 4.4)

- Rename all component files to PascalCase matching exported names
- Move components into feature directories (git/, session/, project/, terminal/, workspace/, ui/, layout/)
- Rename all page files to PascalCase with Page suffix
- Rename all API files to kebab-case
- Update all imports across codebase with corrected relative depths
- Preserve git history via git mv

Quality gates: tsc (pass), eslint (pass), 66/74 tests pass (8 pre-existing failures)
Refs: repo-restructure Task 4.4

apps/web/src/components/ProtectedRoute.test.tsx

@@ -0,0 +1,49 @@
+import { render, screen } from "@testing-library/react";
+import { MemoryRouter, Route, Routes } from "react-router-dom";
+import { describe, expect, it, vi } from "vitest";
+
+import { ProtectedRoute } from "./ProtectedRoute";
+
+const mockUseAuth = vi.fn();
+
+vi.mock("../state/auth", () => ({
+  useAuth: () => mockUseAuth()
+}));
+
+describe("ProtectedRoute", () => {
+  it("shows loading while session is resolving", () => {
+    mockUseAuth.mockReturnValue({ state: "loading" });
+
+    render(
+      <MemoryRouter initialEntries={["/"]}>
+        <ProtectedRoute>
+          <div>private content</div>
+        </ProtectedRoute>
+      </MemoryRouter>
+    );
+
+    expect(screen.getByText("Checking session...")).toBeInTheDocument();
+  });
+
+  it("redirects unauthenticated users to login", () => {
+    mockUseAuth.mockReturnValue({ state: "unauthenticated" });
+
+    render(
+      <MemoryRouter initialEntries={["/settings"]}>
+        <Routes>
+          <Route
+            path="/settings"
+            element={
+              <ProtectedRoute>
+                <div>private content</div>
+              </ProtectedRoute>
+            }
+          />
+          <Route path="/login" element={<div>login page</div>} />
+        </Routes>
+      </MemoryRouter>
+    );
+
+    expect(screen.getByText("login page")).toBeInTheDocument();
+  });
+});