Auth frontend: login, verify, session, and logout

[RandyJDean]

• apiFetch now unwraps the ApiResponder envelope (typed payloads,
  server-authored error messages) and states the cookie contract with
  credentials: same-origin; sample MSW mock updated to match
• New features/auth/: Login page (email -> generic check-your-email
  panel), Verify page (POSTs the emailed token once on mount with a
  StrictMode guard; routes shell accounts to /sign-up), and hooks —
  useSession (moved from lib/api as its comment mandated; 401 resolves
  to null), useRequestLink, useVerifyMagicLink, useLogout
• RequireAuth redirects signed-out visitors to /login and incomplete
  profiles to /sign-up; AppLayout gains a Log out button
• Router mounts /login and /auth/verify under the public layout
• Test infra: auth MSW handlers composed into the server, MemoryRouter
  initialEntries support; page + guard tests cover the happy paths,
  expired links, and shell redirects

Co-Authored-By: Claude Fable 5 noreply@anthropic.com

[RandyJDean]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
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• Auth: enable CSRF protection (SPA double-submit pattern) #51
• Auth: fix verify page stuck on spinner under StrictMode #50
• Auth: document the magic-link feature #49
• Auth frontend: login, verify, session, and logout #48 👈 (View in Graphite)
• Auth: wire Spring Security + Spring Session JDBC end to end #47
• Auth: request-link and verify flows #46
• Auth: core building blocks — token generation, repositories, clock #45
• Auth: add magic-link/session migrations and runtime datasource #44
• main

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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[graphite-app]

Graphite Automations

"Request reviewers once CI passes" took an action on this PR • (07/10/26)

2 reviewers were added to this PR based on Henry Chen's automation.

[graphite-app]

Returns undefined when the backend sends a successful response without a payload field or with invalid JSON, but casts it as type T. If T is not nullable, downstream code will crash at runtime.

For example, if the server returns {success: true, message: "OK"} without payload, or if JSON parsing partially succeeds but produces an object without the payload key, envelope?.payload evaluates to undefined but is typed as T.

if (!envelope?.payload && response.ok) {
  throw new ApiError(
    response.status,
    "Server returned success without payload"
  );
}
return envelope.payload as T;

Alternatively, ensure the type system reflects that payload can be undefined: return envelope?.payload as T | undefined; and update call sites to handle undefined.

Suggested change

	return envelope?.payload as T;
	if (!envelope?.payload && response.ok) {
	throw new ApiError(
	response.status,
	"Server returned success without payload"
	);
	}
	return envelope!.payload as T;

Spotted by Graphite



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