EAS build config + Collaboration UI + i18n updates

- eas.json for Android APK/AAB + iOS builds
- Collaboration page: assign, transfer, claim, subtasks
- Task detail: assignee avatars, subtask progress
- Updated translations (cs,he,ru,ua)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

mobile/eas.json

@@ -0,0 +1,23 @@
+{
+  "cli": { "version": ">= 14.0.0" },
+  "build": {
+    "development": {
+      "developmentClient": true,
+      "distribution": "internal"
+    },
+    "preview": {
+      "distribution": "internal",
+      "android": { "buildType": "apk" }
+    },
+    "production": {
+      "android": { "buildType": "app-bundle" },
+      "ios": { "autoIncrement": true }
+    }
+  },
+  "submit": {
+    "production": {
+      "android": { "serviceAccountKeyPath": "./google-service-account.json" },
+      "ios": { "appleId": "soft.it.enterprise@gmail.com", "ascAppId": "", "appleTeamId": "8U2KKLXVSN" }
+    }
+  }
+}