feat(background): add GET_ACTIVE_TAB_INFO/GET_ACTIVE_TAB_URL to return active tab url and tabId

[cto-new]

Summary

Add a new tab-aware background API that provides the active tab's URL and tabId. It supports both GET_ACTIVE_TAB_INFO and GET_ACTIVE_TAB_URL and returns a single payload with { url, tabId }.

Details

• Implement GET_ACTIVE_TAB_INFO and GET_ACTIVE_TAB_URL handlers in background/index.ts to return { url, tabId, timestamp } with defaults when access is denied
• Add ActiveTabInfo TypeScript interface with url, tabId, timestamp, and optional error; include JSDoc
• Add defensive logging for missing tabs, IDs, or errors; include timestamp
• Ensure backward compatibility by supporting both message names; side panel can request a single payload with { url, tabId }
• No breaking changes; existing consumers remain compatible while gaining richer data