Implement TELEGRAM_ALLOWED_TOPICS for forum topic filtering

[konard]

Summary

This PR implements support for filtering bot commands by Telegram forum topics, in addition to the existing chat filtering. Users can now configure specific topics within supergroups where the bot should respond to commands.

Changes

• Add TELEGRAM_ALLOWED_TOPICS configuration using Links Notation format chatId topicId
• Add parseLinks() and formatLinks() methods to lino library for parsing topic pairs
• Add isTopicAuthorized() function with authorization logic:
  • If chat is in TELEGRAM_ALLOWED_CHATS, all topics in that chat are allowed
  • If specific topic is in TELEGRAM_ALLOWED_TOPICS, only that topic works
  • If neither, access is denied
• Update /help command to:
  • Always be allowed (bypass authorization for diagnostics)
  • Show both chat ID and topic ID in diagnostic information
  • Show configuration hint when in unauthorized topic
• Update /solve, /hive, /limits, /version to use isTopicAuthorized()
• Update dry-run output to show allowed topics configuration
• Update case study documentation with new format and logic

Configuration Format

Uses Links Notation with space-separated chatId topicId pairs:

# Allow specific topic only
TELEGRAM_ALLOWED_TOPICS="(
  -1002975819706 857
)"

# Or with multiple topics
TELEGRAM_ALLOWED_TOPICS="(
  -1002975819706 857
  (-1001234567890 456)
)"

Authorization Logic

1. If chat is in TELEGRAM_ALLOWED_CHATS: All topics in that chat are allowed
2. If topic is in TELEGRAM_ALLOWED_TOPICS: Only that specific topic works
3. /help command: Always allowed (to show chat and topic IDs for configuration)

This design is backward compatible - existing deployments work unchanged.

Test Plan

• Run local lint checks (ESLint, Prettier)
• Test dry-run mode with topic configuration
• Test parseLinks() method with various input formats
• CI checks pass

Fixes #1100

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[konard]

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[konard]

# New - optional topic restrictions within allowed chats
TELEGRAM_ALLOWED_TOPICS="(
  -1002975819706 857
  (-1001234567890 456)
)"

Lets add these, also /help command should show not only chat, but also topic, and should be allowed in all cases, as it is required to see actual topic ids.

If we have access to topic, but not to chat, only topic is working, if we have acces also to chat - that means all topics allowed in the chat, so no need for * syntax.

And everything will be backward compatible.

Links syntax allows omitting ( ) on the end of lines, so in both cases pair of ids (references in links notation) will be parsed as single link.

[konard]

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[konard]

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