Rebrand app identifier and IPA name from Ditto to Agora

Renames the Capacitor app identifier from pub.agora.app to
spot.agora.app and cleans up Ditto-branded artifacts that don't refer
to upstream Ditto-the-project or Ditto-stack services.

App identifier (pub.agora.app -> spot.agora.app):
- capacitor.config.ts appId
- android applicationId, namespace, package_name string, custom_url_scheme
- iOS PRODUCT_BUNDLE_IDENTIFIER (Debug + Release)
- public/.well-known/assetlinks.json package_name
- public/.well-known/apple-app-site-association app id
- Info.plist BGTaskSchedulerPermittedIdentifiers and the matching
  Swift bgTaskIdentifier (previously mismatched: plist said
  pub.agora.app.notification-refresh, Swift said
  pub.ditto.app.notification-refresh, so background refresh would
  silently fail to register)
- src/lib/helpContent.ts Zapstore URLs
- .gitlab-ci.yml --package_name for fastlane supply

Android Java package (pub.ditto.app -> spot.agora.app):
- Move android/app/src/main/java/pub/ditto/app/ ->
  android/app/src/main/java/spot/agora/app/ (4 files: MainActivity,
  DittoNotificationPlugin, NostrPoller, NotificationRelayService)
- Update package declarations to match the new Android namespace
  (was a hard build failure with namespace = spot.agora.app)
- Update proguard -keep rule
- Update NotificationRelayService ACTION_FETCH intent string
  pub.ditto.app.ACTION_FETCH -> spot.agora.app.ACTION_FETCH

Fastlane (pub.ditto.app -> spot.agora.app):
- Appfile, Matchfile, Fastfile provisioning profile specifiers.
  Matchfile still points at Soapbox's certificates git repo; a new
  match repo with certs for spot.agora.app is required before iOS CI
  signing works.

IPA artifact name (Ditto.ipa -> Agora.ipa):
- Fastfile output_name and matching CI artifact paths
- .gitlab-ci.yml: artifacts/Ditto.ipa references and the GitLab
  Generic Packages path from /packages/generic/ditto/ ->
  /packages/generic/agora/ (matches how APK/AAB are already
  published). Existing release artifacts at the old path remain
  reachable; new releases land at the new path.

Release-notes script fallback (Ditto vX.Y.Z -> Agora vX.Y.Z):
- scripts/extract-release-notes.mjs fallback used as the App Store /
  Play Store 'What's New' blurb when a changelog section has no
  summary.

manifest.webmanifest:
- Update related_applications Play Store entry to spot.agora.app.
- Remove the iTunes related_applications entry that pointed at
  the existing Ditto App Store listing; not applicable to Agora
  until Agora has its own listing.

Capacitor sync incidentals:
- npm run cap:sync picked up @capacitor/barcode-scanner registration
  that had been missed in a prior plugin install
  (android/app/capacitor.build.gradle, capacitor.settings.gradle,
  ios/App/CapApp-SPM/Package.swift).

Intentionally NOT touched:
- ditto.json filename, DittoConfigSchema, DittoConfig, and JSDoc
  references to ditto.json. The config-system shape is shared with
  upstream Ditto by design.
- relay.ditto.pub, blossom.ditto.pub, ditto.pub/api/* and other
  Ditto-stack services Agora actively consumes.
- The DittoNotificationPlugin Android/iOS class name, the
  DittoNotification JS bridge name, ditto_notification_config
  SharedPreferences keys, ic_stat_ditto drawables, and the
  DittoBridgeViewController. Renaming requires a coordinated
  JS-side rename plus a SharedPreferences migration or existing
  users on the Ditto fork lose their notification config on upgrade.
- Ditto references in skill docs, NIP.md kind comments, README, and
  zapstore.yaml attribution \u2014 those correctly describe the upstream
  Ditto project that Agora forked from.

Follow-ups required before CI succeeds end-to-end (out of scope here):
- Stand up a new fastlane match git repo containing certs +
  provisioning profiles for spot.agora.app, or update Matchfile
  git_url to point at it.
- Register spot.agora.app in App Store Connect for team GZLTTH5DLM
  and create a new App Store listing.
- Create a new Google Play Console listing for spot.agora.app
  (package name is immutable per app on Play; the existing
  pub.agora.app listing cannot be reused).
- Re-publish to Zapstore under spot.agora.app so the URLs in
  helpContent.ts resolve.

.gitlab-ci.yml

@@ -104,7 +104,7 @@ release-notes:
     # release-notes.md is the full section (summary + bulleted lists), used as
     # the GitLab Release description. release-notes-summary.txt is the leading
     # plaintext paragraph only, used as the App Store / Play Store release
-    # blurb. Falls back to "Ditto vX.Y.Z" when the section has no summary.
+    # blurb. Falls back to "Agora vX.Y.Z" when the section has no summary.
     - mkdir -p artifacts
     - node scripts/extract-release-notes.mjs "$CI_COMMIT_TAG" > artifacts/release-notes.md
     - node scripts/extract-release-notes.mjs "$CI_COMMIT_TAG" --summary > artifacts/release-notes-summary.txt
@@ -280,27 +280,27 @@ build-ipa:
       ios/App/App.xcodeproj/project.pbxproj
 
     # Run match (cert verify + decrypt) and build_app to produce the IPA.
-    # build_app writes ./artifacts/Ditto.ipa relative to the project root.
+    # build_app writes ./artifacts/Agora.ipa relative to the project root.
     - cd ios
     - fastlane build_ipa
     - cd ..
 
     # Move the IPA to a stable name in the artifact directory.
     - ls -lh artifacts/
-    - test -f artifacts/Ditto.ipa
+    - test -f artifacts/Agora.ipa
 
     # Upload to the Generic Packages registry for a stable public download URL,
     # mirroring how build-apk publishes the APK and AAB.
     - |
       curl --fail --header "JOB-TOKEN: ${CI_JOB_TOKEN}" \
-        --upload-file "artifacts/Ditto.ipa" \
-        "${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/packages/generic/ditto/${CI_COMMIT_TAG}/Ditto-${CI_COMMIT_TAG}.ipa"
+        --upload-file "artifacts/Agora.ipa" \
+        "${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/packages/generic/agora/${CI_COMMIT_TAG}/Agora-${CI_COMMIT_TAG}.ipa"
   after_script:
     # Wipe the API key so nothing sensitive sticks around between jobs.
     - rm -f "$HOME/.private_keys"/AuthKey_*.p8 || true
   artifacts:
     paths:
-      - artifacts/Ditto.ipa
+      - artifacts/Agora.ipa
     expire_in: 90 days
 
 release:
@@ -333,8 +333,8 @@ release:
         - name: Agora-${CI_COMMIT_TAG}.aab
           url: ${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/packages/generic/agora/${CI_COMMIT_TAG}/Agora-${CI_COMMIT_TAG}.aab
           link_type: package
-        - name: Ditto-${CI_COMMIT_TAG}.ipa
-          url: ${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/packages/generic/ditto/${CI_COMMIT_TAG}/Ditto-${CI_COMMIT_TAG}.ipa
+        - name: Agora-${CI_COMMIT_TAG}.ipa
+          url: ${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/packages/generic/agora/${CI_COMMIT_TAG}/Agora-${CI_COMMIT_TAG}.ipa
           link_type: package
 
 publish-zapstore:
@@ -395,7 +395,7 @@ publish-google-play:
     - >-
       fastlane supply
       --aab artifacts/Agora.aab
-      --package_name pub.agora.app
+      --package_name spot.agora.app
       --track production
       --json_key /tmp/play-service-account.json
       --metadata_path android/fastlane/metadata/android
@@ -446,7 +446,7 @@ publish-app-store:
     # a JSON descriptor; we pass the API key inline via the Fastfile.
     - unset APP_STORE_CONNECT_API_KEY_PATH || true
   script:
-    - test -f artifacts/Ditto.ipa
+    - test -f artifacts/Agora.ipa
     - test -f artifacts/release-notes-summary.txt
 
     # Use the release summary paragraph as the App Store "What's New" text.
@@ -458,7 +458,7 @@ publish-app-store:
     - echo "-------------------------"
 
     # Submit the prebuilt IPA from build-ipa to App Store Connect for review.
-    - export IPA_PATH="$CI_PROJECT_DIR/artifacts/Ditto.ipa"
+    - export IPA_PATH="$CI_PROJECT_DIR/artifacts/Agora.ipa"
     - cd ios
     - fastlane submit_release
   after_script: