Tests: add flutter_test and money formatting tests

The template counter test could never compile (no flutter_test dev
dependency, no MyApp). Replace it with unit tests for formatMoney
(INR byte-identical to the old formatter, AED, BHD) and currency parsing.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

pubspec.lock

@@ -33,6 +33,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.13.1"
+  boolean_selector:
+    dependency: transitive
+    description:
+      name: boolean_selector
+      sha256: "8aab1771e1243a5063b8b0ff68042d67334e3feab9e95b9490f9a6ebf73b42ea"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.2"
   characters:
     dependency: transitive
     description:
@@ -61,10 +69,10 @@ packages:
     dependency: transitive
     description:
       name: clock
-      sha256: e51d50bca3217c9a9fa2b41a30e4a38971133f5f9ec7a3d57bae095007f1d28e
+      sha256: fddb70d9b5277016c77a80201021d40a2247104d9f4aa7bab7157b7e3f05b84b
       url: "https://pub.dev"
     source: hosted
-    version: "1.1.3"
+    version: "1.1.2"
   collection:
     dependency: transitive
     description:
@@ -105,6 +113,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.0.9"
+  fake_async:
+    dependency: transitive
+    description:
+      name: fake_async
+      sha256: "5368f224a74523e8d2e7399ea1638b37aecfca824a3cc4dfdf77bf1fa905ac44"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.3.3"
   ffi:
     dependency: transitive
     description:
@@ -198,6 +214,11 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.0.35"
+  flutter_test:
+    dependency: "direct dev"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
   flutter_web_plugins:
     dependency: transitive
     description: flutter
@@ -363,6 +384,30 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "4.12.0"
+  leak_tracker:
+    dependency: transitive
+    description:
+      name: leak_tracker
+      sha256: "33e2e26bdd85a0112ec15400c8cbffea70d0f9c3407491f672a2fad47915e2de"
+      url: "https://pub.dev"
+    source: hosted
+    version: "11.0.2"
+  leak_tracker_flutter_testing:
+    dependency: transitive
+    description:
+      name: leak_tracker_flutter_testing
+      sha256: "1dbc140bb5a23c75ea9c4811222756104fbcd1a27173f0c34ca01e16bea473c1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.10"
+  leak_tracker_testing:
+    dependency: transitive
+    description:
+      name: leak_tracker_testing
+      sha256: "8d5a2d49f4a66b49744b23b018848400d23e54caf9463f4eb20df3eb8acb2eb1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.2"
   lints:
     dependency: transitive
     description:
@@ -371,6 +416,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "4.0.0"
+  matcher:
+    dependency: transitive
+    description:
+      name: matcher
+      sha256: dc0b7dc7651697ea4ff3e69ef44b0407ea32c487a39fff6a4004fa585e901861
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.12.19"
   material_color_utilities:
     dependency: transitive
     description:
@@ -528,6 +581,22 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.10.2"
+  stack_trace:
+    dependency: transitive
+    description:
+      name: stack_trace
+      sha256: "8b27215b45d22309b5cddda1aa2b19bdfec9df0e765f2de506401c071d38d1b1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.12.1"
+  stream_channel:
+    dependency: transitive
+    description:
+      name: stream_channel
+      sha256: "969e04c80b8bcdf826f8f16579c7b14d780458bd97f56d107d3950fdbeef059d"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.4"
   string_scanner:
     dependency: transitive
     description:
@@ -544,6 +613,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.2.2"
+  test_api:
+    dependency: transitive
+    description:
+      name: test_api
+      sha256: "949a932224383300f01be9221c39180316445ecb8e7547f70a41a35bf421fb9e"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.7.11"
   typed_data:
     dependency: transitive
     description:
@@ -640,6 +717,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.2.0"
+  vm_service:
+    dependency: transitive
+    description:
+      name: vm_service
+      sha256: "89b11d62e1040ee681af3b4f1c97a803ecbf010c6e8b9c5896ee5b08c3bf7b78"
+      url: "https://pub.dev"
+    source: hosted
+    version: "15.4.0"
   web:
     dependency: transitive
     description: