fix(extensions): comprehensive name resolution and error handling improvements

- Add shared _resolve_installed_extension helper for ID/display name resolution
  with proper ambiguous name handling (shows table of matches)
- Add _resolve_catalog_extension helper for catalog lookups by ID or display name
- Update enable/disable/update/remove commands to use name resolution helpers
- Fix extension_info to handle catalog errors gracefully:
  - Fallback to local installed info when catalog unavailable
  - Distinguish "catalog unavailable" from "not found in catalog"
  - Support display name lookup for both installed and catalog extensions
- Use resolved display names in all status messages for consistency
- Extract _print_extension_info helper for DRY catalog info printing

Addresses reviewer feedback:
- Ambiguous name handling in enable/disable/update
- Catalog error fallback for installed extensions
- UX message clarity (catalog unavailable vs not found)
- Resolved ID in status messages

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: iamaeroplane