Implement Journal auth: passkeys + magic links, no passwords

Auth flows:
- Passkey registration: email + username → WebAuthn create → account + session
- Passkey login: WebAuthn get → session (instant, no form)
- Magic link fallback: email → token → verify link → session
- Logout via POST /auth/logout

Infrastructure:
- auth.server.ts: WebAuthn (SimpleWebAuthn), magic tokens, cookie sessions
- DB schema: credentials (WebAuthn), magic_tokens tables, no password_hash
- Session middleware via getSessionUser()

Pages:
- /auth/register — email + username + passkey creation
- /auth/login — passkey button + magic link fallback
- /auth/verify — magic link token verification
- /users/:username — public profile page
- Home page shows auth state (register/signin or welcome)

Dynamic imports for @simplewebauthn/browser to avoid SSR issues.
Magic links logged to console in dev (email integration later).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/journal/package.json

@@ -11,22 +11,25 @@
     "lint": "eslint ."
   },
   "dependencies": {
-    "@trails-cool/db": "workspace:*",
-    "@trails-cool/ui": "workspace:*",
-    "@trails-cool/types": "workspace:*",
-    "@trails-cool/map": "workspace:*",
-    "@trails-cool/gpx": "workspace:*",
-    "@trails-cool/i18n": "workspace:*",
-    "drizzle-orm": "catalog:",
-    "react": "catalog:",
-    "react-dom": "catalog:",
-    "react-router": "catalog:",
     "@react-router/node": "catalog:",
     "@react-router/serve": "catalog:",
-    "isbot": "^5.1.0"
+    "@simplewebauthn/browser": "^13.3.0",
+    "@simplewebauthn/server": "^13.3.0",
+    "@trails-cool/db": "workspace:*",
+    "@trails-cool/gpx": "workspace:*",
+    "@trails-cool/i18n": "workspace:*",
+    "@trails-cool/map": "workspace:*",
+    "@trails-cool/types": "workspace:*",
+    "@trails-cool/ui": "workspace:*",
+    "drizzle-orm": "catalog:",
+    "isbot": "^5.1.0",
+    "react": "catalog:",
+    "react-dom": "catalog:",
+    "react-router": "catalog:"
   },
   "devDependencies": {
     "@react-router/dev": "catalog:",
+    "@simplewebauthn/types": "^12.0.0",
     "@tailwindcss/vite": "catalog:",
     "@types/react": "catalog:",
     "@types/react-dom": "catalog:",