chore(deps): drop unused cupertino_icons + tslib

Both verified unused at the source/config level (Fable #461 +
audit note #460):

- cupertino_icons: zero `CupertinoIcons` / cupertino imports in
  flutter_client/lib/. Pure `flutter create` template residue;
  the design system mandates Lucide.
- tslib: web/tsconfig.json does not set `importHelpers: true`,
  so TypeScript inlines helpers per-file. Declared peer with no
  runtime consumer.

`npm uninstall tslib --save-dev` updated package-lock.json
surgically (8 lines removed for the tslib entry only). No other
deps disturbed.

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

flutter_client/pubspec.yaml

@@ -33,7 +33,6 @@ dependencies:
   # until either lib bumps win32 to 6.x.
   package_info_plus: ^8.3.1
   pub_semver: ^2.1.4
-  cupertino_icons: ^1.0.8
   path_provider: ^2.1.5
   drift: ^2.18.0
   drift_flutter: ^0.2.0

web/package-lock.json

@@ -25,7 +25,6 @@
         "svelte": "^5.1.9",
         "svelte-check": "^4.0.5",
         "tailwindcss": "^3.4.14",
-        "tslib": "^2.8.0",
         "typescript": "^5.6.3",
         "vite": "^5.4.10",
         "vitest": "^2.1.4"
@@ -3764,13 +3763,6 @@
       "dev": true,
       "license": "Apache-2.0"
     },
-    "node_modules/tslib": {
-      "version": "2.8.1",
-      "resolved": "https://registry.npmjs.org/tslib/-/tslib-2.8.1.tgz",
-      "integrity": "sha512-oJFu94HQb+KVduSUQL7wnpmqnfmLsOA/nAh6b6EH0wCEoK0/mPeXU6c3wKDV83MkOuHPRHtSXKKU99IBazS/2w==",
-      "dev": true,
-      "license": "0BSD"
-    },
     "node_modules/typescript": {
       "version": "5.9.3",
       "resolved": "https://registry.npmjs.org/typescript/-/typescript-5.9.3.tgz",

web/package.json

@@ -24,7 +24,6 @@
     "svelte": "^5.1.9",
     "svelte-check": "^4.0.5",
     "tailwindcss": "^3.4.14",
-    "tslib": "^2.8.0",
     "typescript": "^5.6.3",
     "vite": "^5.4.10",
     "vitest": "^2.1.4"