Add Playwright fixtures with 5 test user types for e2e tests

Creates test infrastructure to enable previously skipped e2e tests:
- Onboarding user (no period data) for setup flow tests
- Established user (period 14 days ago) for normal usage tests
- Calendar user (with calendarToken) for ICS feed tests
- Garmin user (valid tokens) for connected state tests
- Garmin expired user (expired tokens) for expiry warning tests

Also fixes ICS feed route to strip .ics suffix from Next.js dynamic
route param, adds calendarToken to /api/user response, and sets
viewRule on users collection for unauthenticated ICS access.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/app/api/calendar/[userId]/[token].ics/route.ts

@@ -14,11 +14,13 @@ interface RouteParams {
 }
 
 export async function GET(_request: NextRequest, { params }: RouteParams) {
-  const { userId, token } = await params;
+  const { userId, token: rawToken } = await params;
+  // Strip .ics suffix if present (Next.js may include it in the param)
+  const token = rawToken.endsWith(".ics") ? rawToken.slice(0, -4) : rawToken;
+  const pb = createPocketBaseClient();
 
   try {
     // Fetch user from database
-    const pb = createPocketBaseClient();
     const user = await pb.collection("users").getOne(userId);
 
     // Check if user has a calendar token set