Clear push notifications when one is opened

[caydyan]

Fixes #428

Summary

• Add clearAllNotifications() to the Sphinx notification manager abstraction and Android implementation.
• Clear the app notification tray when MainActivity is launched or re-opened from a push notification intent.
• Consume the chat_id extra after handling it so the notification navigation is not processed again later, and accept string/int/long chat IDs.

Validation

• git diff --check
• JAVA_HOME=/opt/homebrew/opt/openjdk@17/libexec/openjdk.jdk/Contents/Home ANDROID_HOME=/tmp/codex-android-sdk-real ./gradlew :sphinx:application:data:concepts:concept-sphinx-notification-manager:compileKotlin --no-daemon
• JAVA_HOME=/opt/homebrew/opt/openjdk@17/libexec/openjdk.jdk/Contents/Home ANDROID_HOME=/tmp/codex-android-sdk-real ./gradlew :sphinx:application:data:features:feature-sphinx-notification-manager:compileDebugKotlin --no-daemon
• Attempted JAVA_HOME=/opt/homebrew/opt/openjdk@17/libexec/openjdk.jdk/Contents/Home ANDROID_HOME=/tmp/codex-android-sdk-real ./gradlew :sphinx:activity:main:activitymain:compileDebugKotlin --no-daemon; the local build repeatedly progressed through the modified notification modules and into activitymain/dashboard data binding, then failed while resolving remote runtime dependencies because Maven/Google/GitHub raw downloads intermittently terminated TLS handshakes. No source compile error was observed before those dependency-resolution failures.

Bounty payout address: bc1qev5ant33v5y89qqjvcf4mh9hlax5svqf5xd7gc

[caydyan]

Current-head validation rerun on 2f34a4c6d9f8caf6f26548411cc54275eb9c2a2d:

• git diff --check origin/master...HEAD
• JAVA_HOME=/opt/homebrew/opt/openjdk@17/libexec/openjdk.jdk/Contents/Home ANDROID_HOME=/tmp/codex-android-sdk-real ./gradlew :sphinx:application:data:concepts:concept-sphinx-notification-manager:compileKotlin --no-daemon (build successful)
• JAVA_HOME=/opt/homebrew/opt/openjdk@17/libexec/openjdk.jdk/Contents/Home ANDROID_HOME=/tmp/codex-android-sdk-real ./gradlew :sphinx:application:data:features:feature-sphinx-notification-manager:compileDebugKotlin --no-daemon (build successful)

I also retried :sphinx:activity:main:activitymain:compileDebugKotlin; it progressed through 767 tasks and failed while downloading androidx.lifecycle:lifecycle-viewmodel:2.2.0 from dl.google.com because the remote host terminated the TLS handshake, not from a source compile error in this PR. Local worktree is clean after the rerun.

[caydyan]

Follow-up validation on 2f34a4c6d9f8caf6f26548411cc54275eb9c2a2d: the broader activity module compile now passes locally.

Additional validation:

• git diff --check origin/master...HEAD passed after fetching origin/master.
• JAVA_HOME=/opt/homebrew/opt/openjdk@17/libexec/openjdk.jdk/Contents/Home ANDROID_HOME=/tmp/codex-android-sdk-real ./gradlew :sphinx:activity:main:activitymain:compileDebugKotlin --no-daemon --stacktrace --console=plain -Pkapt.use.worker.api=false -Dkotlin.compiler.execution.strategy=in-process -Dorg.gradle.jvmargs=... passed.
• Result: BUILD SUCCESSFUL in 2m 47s; 1504 actionable tasks: 276 executed, 33 from cache, 1195 up-to-date.

The extra Gradle flags are local toolchain flags for this checkout's older KAPT setup on JDK 17; no source changes were needed, and the local worktree is clean.