chore(deps): Tier A cross-ecosystem patch/minor sweep

No expected behavior changes; CI verifies. Tracked in Fable #463
under audit note #460.

Flutter (pubspec.yaml):
- flutter_secure_storage ^10.1.0 → ^10.2.0
- mocktail ^1.0.4 → ^1.0.5

Web (package.json + package-lock.json):
- @sveltejs/adapter-static ^3.0.6 → ^3.0.10
- @types/node ^25.6.0 → ^25.9.1
- autoprefixer ^10.4.20 → ^10.5.0
- postcss ^8.4.49 → ^8.5.15
- svelte-check ^4.0.5 → ^4.4.8

Tools (package.json + package-lock.json):
- sharp ^0.33.5 → ^0.34.5 (the lockfile diff is large because
  sharp ships pre-built binaries for many platform/arch combos;
  each version revs all those entries)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

flutter_client/pubspec.yaml

@@ -19,7 +19,7 @@ dependencies:
   # interruption/becoming-noisy itself (just_audio does not). Same author
   # as just_audio/audio_service so versions track together.
   audio_session: ^0.2.3
-  flutter_secure_storage: ^10.1.0
+  flutter_secure_storage: ^10.2.0
   go_router: ^17.2.3
   flutter_svg: ^2.0.16
   # Lucide icon set (design system mandates Lucide, not Material).
@@ -58,7 +58,7 @@ dev_dependencies:
   flutter_test:
     sdk: flutter
   flutter_lints: ^6.0.0
-  mocktail: ^1.0.4
+  mocktail: ^1.0.5
   drift_dev: ^2.18.0
   build_runner: ^2.4.13