Build Android release APK; fix release build and bump sentry_flutter

Two build-blocking issues fixed to get a release APK building at all:

- flutter_local_notifications (V3-06) requires core library desugaring below API 33; enabled it and added the desugar_jdk_libs dependency.
- sentry_flutter 8.14.2's bundled Kotlin plugin declares languageVersion 1.6, incompatible with this project's Kotlin 2.4.0 toolchain. Bumped to sentry_flutter ^9.0.0 (resolved 9.27.0), which builds clean; left three copyWith deprecation infos from the v9 API as a follow-up, not blocking.

Signed with the debug keystore (release signingConfig still points at debug -- no release signing config exists yet, matches the existing TODO in build.gradle.kts). app-release.apk committed directly (68.7MB, force-added past .gitignore's build/ exclusion) per request, so it can be pushed once a remote exists.

pubspec.lock

@@ -523,26 +523,10 @@ packages:
     dependency: transitive
     description:
       name: jni
-      sha256: f038e58b4dc2c9037f50e233175086337e0b305e356d28211bf55f21c504cbd3
+      sha256: d2c361082d554d4593c3012e26f6b188f902acd291330f13d6427641a92b3da1
       url: "https://pub.dev"
     source: hosted
-    version: "1.0.3"
-  jni_flutter:
-    dependency: transitive
-    description:
-      name: jni_flutter
-      sha256: "7b717011ea40d04fd47c2731d3d1d36eb99eba3435c2753d62489e8c3c9991d5"
-      url: "https://pub.dev"
-    source: hosted
-    version: "1.0.2"
-  jni_util:
-    dependency: transitive
-    description:
-      name: jni_util
-      sha256: "1ba86da04a5f2bf18fde2edb235587e70c5b0fc5bd4ba955f46b00942c3fc35f"
-      url: "https://pub.dev"
-    source: hosted
-    version: "1.0.0"
+    version: "0.14.2"
   json_annotation:
     dependency: transitive
     description:
@@ -707,10 +691,10 @@ packages:
     dependency: transitive
     description:
       name: path_provider_android
-      sha256: "69cbd515a62b94d32a7944f086b2f82b4ac40a1d45bebfc00813a430ab2dabcd"
+      sha256: "149441ca6e4f38193b2e004c0ca6376a3d11f51fa5a77552d8bd4d2b0c0912ba"
       url: "https://pub.dev"
     source: hosted
-    version: "2.3.1"
+    version: "2.2.23"
   path_provider_foundation:
     dependency: transitive
     description:
@@ -891,18 +875,18 @@ packages:
     dependency: transitive
     description:
       name: sentry
-      sha256: "599701ca0693a74da361bc780b0752e1abc98226cf5095f6b069648116c896bb"
+      sha256: c2ecd8abe82e63cdcb6947f71320612ced56e10ba94db7529d85cc02be47cb3b
       url: "https://pub.dev"
     source: hosted
-    version: "8.14.2"
+    version: "9.27.0"
   sentry_flutter:
     dependency: "direct main"
     description:
       name: sentry_flutter
-      sha256: "5ba2cf40646a77d113b37a07bd69f61bb3ec8a73cbabe5537b05a7c89d2656f8"
+      sha256: ec89cc6ba939ca19155ea83900d9740a36544f50b3b6baf265518e3348fb0f50
       url: "https://pub.dev"
     source: hosted
-    version: "8.14.2"
+    version: "9.27.0"
   share_plus:
     dependency: "direct main"
     description: