style(13-03): apply Prettier formatting across repo

Mechanical reformat — no logic changes. 398 files changed, 19125
insertions(+), 16457 deletions(-). Prettier 3.8.4 with .prettierrc
(singleQuote:true, semi:true, tabWidth:2, trailingComma:all,
printWidth:100). Isolated per D-13-08 for reviewability.

.planning/milestones/v1.0-phases/03-event-write-back-pwa-install/03-REVIEW-FIX.iter3.md

@@ -16,11 +16,13 @@ status: all_fixed
 **Iteration:** 2
 
 **Summary:**
+
 - Findings in scope: 8 (fix_scope: all — Critical + Warning + Info)
 - Fixed: 8
 - Skipped: 0
 
 All fixes verified with `tsc --noEmit` AND the full vitest suite in BOTH apps:
+
 - `apps/api`: 108 tests pass (was 103 baseline; +5 new regression tests)
 - `apps/pwa`: 145 tests pass (was 141 baseline; +4 new regression tests)
 - Typecheck clean in both packages.