chore(release): bump to 0.30.4

Patch release: one behavioural fix (removal of the dead
CodelessDebugLogEnabled manifest entry) plus documentation changes. No API
surface change.

pubspec.yaml and ios/facebook_app_events.podspec are kept in sync per
CONTRIBUTING.md. The CHANGELOG's "Unreleased" heading becomes "## 0.30.4"
because build_deploy.yml extracts release notes by matching a literal
"## <version>" heading and fails the release job if it finds none.

Graph API pin left at v24.0. The release-time check now recorded in
CONTRIBUTING.md does flag that the current latest is v26.0, but bumping the
pin is a behavioural change that deserves its own PR rather than riding along
in a release commit.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: DennisAlund

CHANGELOG.md

@@ -1,4 +1,4 @@
-## Unreleased
+## 0.30.4
 
 - **Remove the `com.facebook.sdk.CodelessDebugLogEnabled` meta-data from the plugin's Android manifest.** It has been there since the first release and had no effect: in Facebook Android SDK 18.x the flag is read into `FacebookSdk.getCodelessDebugLogEnabled()` and nothing in the SDK reads that getter. Codeless event setup is gated server-side by Meta's fetched app settings (`codelessEventsEnabled` / `getCodelessSetupEnabled()`), not by this flag. Because library manifests merge into the host app, the entry also forced any app that wanted the key set to `false` to add `tools:replace` to win the merge — that workaround is no longer needed and can be removed.
 - **Docs:** the README no longer advises enabling codeless debug logging for debugging (the flags are inert on both platforms; `setDebugLoggingEnabled` is the switch that does something), and `CONTRIBUTING.md` now records the pinned Graph API version as a release-time check with the three places the literal appears.

ios/facebook_app_events.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = 'facebook_app_events'
-  s.version          = '0.30.3'
+  s.version          = '0.30.4'
   s.summary          = 'Flutter plugin for Facebook Analytics and App Events'
   s.description      = <<-DESC
 Flutter plugin for Facebook Analytics and App Events

pubspec.yaml

@@ -1,7 +1,7 @@
 name: facebook_app_events
 description: Flutter plugin for Facebook App Events, an app measurement
   solution that provides insight on app usage and user engagement in Facebook Analytics.
-version: 0.30.3
+version: 0.30.4
 homepage: https://oddb.it/app-events-pubspec
 repository: https://github.com/oddbit/flutter_facebook_app_events