feat(feedback): prompt for a store review after successful sessions

Add expo-store-review (SDK 54-matched via `expo install`) and wire a
one-time in-app rating prompt into the SSE busy->idle "session completed"
transition in stores/events.ts — the same signal that already drives the
"Task completed" notification, so it only fires on genuine success, never
on session.error.

State (success count, one-time "asked" flag) persists in expo-secure-store,
mirroring the consent pattern in telemetry.ts. The threshold check is split
into store-review-policy.ts, free of expo imports, so it's unit-testable
with plain `node --test` (same split as buildAuth in auth.ts).

F-Droid/Play-Services-absent safety comes from the library itself:
StoreReview.isAvailableAsync() resolves false there, so requestReview() is
never called and there's no store-URL fallback configured in app.json.

package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "@opencode-ai/mobile",
-  "version": "0.4.3",
+  "version": "0.4.7",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@opencode-ai/mobile",
-      "version": "0.4.3",
+      "version": "0.4.7",
       "dependencies": {
         "@expo/vector-icons": "^15.0.3",
         "@gorhom/bottom-sheet": "5.2.8",
@@ -26,6 +26,7 @@
         "expo-secure-store": "~15.0.8",
         "expo-speech-recognition": "3.0.1",
         "expo-status-bar": "~3.0.9",
+        "expo-store-review": "~9.0.9",
         "react": "19.1.0",
         "react-native": "0.81.5",
         "react-native-gesture-handler": "~2.28.0",
@@ -5254,6 +5255,16 @@
         "react-native": "*"
       }
     },
+    "node_modules/expo-store-review": {
+      "version": "9.0.9",
+      "resolved": "https://registry.npmjs.org/expo-store-review/-/expo-store-review-9.0.9.tgz",
+      "integrity": "sha512-99vS7edXlKzPcdjrzVlMQWc4zOyq4khQfFjhNqJgpGP+AgRn4U0LaZkHIrVjmzolryD3rcHJSiUQH9Vi0sD0MQ==",
+      "license": "MIT",
+      "peerDependencies": {
+        "expo": "*",
+        "react-native": "*"
+      }
+    },
     "node_modules/expo/node_modules/@expo/cli": {
       "version": "54.0.24",
       "resolved": "https://registry.npmjs.org/@expo/cli/-/cli-54.0.24.tgz",