Implement Telegram documentation updates checker

[swimmwatch]

Closes #181

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[Copilot]

Pull Request Overview

This PR implements a Telegram documentation updates checker that monitors changes to the Telegram Mini App documentation and creates GitHub issues when updates are detected. The solution uses a custom GitHub Action built around the webchanges utility to track documentation changes.

Key changes:

• Creates a scheduled workflow that checks for Telegram documentation updates every 30 minutes
• Implements a custom GitHub Action that wraps the webchanges utility with custom reporters and filters
• Adds functionality to create GitHub issues automatically when documentation changes are detected

Reviewed Changes

Copilot reviewed 3 out of 4 changed files in this pull request and generated 4 comments.

File	Description
.github/workflows/check-update.yml	Defines the scheduled workflow to check Telegram documentation updates and create GitHub issues
.github/actions/webchanges/hooks.py	Implements custom GitHub issue reporter and text filtering functionality for the webchanges utility
.github/actions/webchanges/action.yml	Defines the composite GitHub Action that sets up and runs the webchanges tool with caching

Comments suppressed due to low confidence (1)

.github/actions/webchanges/action.yml:26

• The webchanges version 3.30.0 may not exist. Please verify this is a valid version number for the webchanges package.

        echo "WEBCHANGES_VERSION=3.30.0" >> $GITHUB_ENV