FCE-2578: Add EAS Build

[MiloszFilimowski]

Description

• Added eas build, which builds and creates a TestFlight release along withan Android APK build.

Motivation and Context

• We need builds for testing

Documentation impact

• Documentation update required
• Documentation updated in another PR
• No documentation update required

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to
  not work as expected)

[linear]

FCE-2578 Add EAS Build

[github-actions]

Download links
Android - 1.0.0 (93): https://expo.dev/artifacts/eas/s9xJKkDd9U78yqeJfh93wb.apk
iOS - 1.0.0 (113): https://testflight.apple.com/v1/app/6711353226

[Copilot]

Pull request overview

This PR wires up Expo Application Services (EAS) build and submission for the fishjam-chat mobile example, and switches the React Native WebRTC dependency from a Git commit to a published npm version to support the new build pipeline.

Changes:

• Move @fishjam-cloud/react-native-webrtc from a GitHub commit reference to the npm-published 0.25.0 and update the lockfile accordingly.
• Add EAS-related configuration and scripts for the examples/mobile-client/fishjam-chat app (eas.json, updated app.json, and new eas-build-pre-install/prebuild scripts).
• Introduce a GitHub Actions workflow (mobile_eas_build.yaml) that, on labeled PRs, builds the mobile app via EAS, submits the iOS build to TestFlight, and comments build links on the PR.

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
yarn.lock	Updates lockfile entry to use @fishjam-cloud/react-native-webrtc from npm at version 0.25.0 instead of a GitHub commit.
packages/mobile-client/package.json	Points the mobile client package to @fishjam-cloud/react-native-webrtc version 0.25.0 from npm, aligning with the new lockfile entry.
examples/mobile-client/fishjam-chat/package.json	Adds EAS build hook scripts (eas-build-pre-install, prebuild) to install deps, build the monorepo, and clean/prebuild native projects before EAS runs.
examples/mobile-client/fishjam-chat/eas.json	Introduces EAS CLI/build/submit configuration, including build profiles and App Store Connect app ID for production submission.
examples/mobile-client/fishjam-chat/app.json	Adjusts iOS and Android bundle identifiers, adds encryption declaration, and configures EAS extras for project ID and the iOS Screen Broadcast extension.
.github/workflows/mobile_eas_build.yaml	Adds a PR-label-triggered macOS workflow that runs EAS build for both platforms, submits the iOS build to TestFlight, and posts PR comments with build metadata and download links.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 8 comments.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 9 comments.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[github-actions]

Download links
Android - 1.0.0 (95): https://expo.dev/artifacts/eas/2YhAGU9sjNekq6TPEVo7eY.apk
iOS - 1.0.0 (115): https://testflight.apple.com/v1/app/6711353226