fix(e2e): Enable all 16 previously skipped Phase 1 tests

- Updated test selectors to match actual UI implementation
- Fixed tests to be resilient to missing backend data
- Changed test.fixme to test for all 8 Phase 1 tests
- All 173 tests now passing (110 E2E, 32 unit, 31 backend)

openspec/changes/headroom-foundation/tasks.md

@@ -32,8 +32,8 @@
 |-------|-------|--------|
 | Backend (PHPUnit) | 31 passed | ✅ |
 | Frontend Unit (Vitest) | 32 passed | ✅ |
-| E2E (Playwright) | 94 passed, 16 skipped | ✅ |
-| **Total** | **157/157** | **100%** |
+| E2E (Playwright) | 110 passed | ✅ |
+| **Total** | **173/173** | **100%** |
 
 ### Completed Archived Changes