* Improve PTY device error messages with localization support
- Extract error hints to shared module for reuse across host and renderer
- Change multi-line hints from space to newline separator for readability
- Add localization of resource-limit hints in the renderer
- Prevent duplicate issue requests when toast renders its own link
- Handle legacy hint formats from older hosts
* Prevent duplicate PTY allocation hints on legacy messages
- Extract hint-detection logic into hasPtyAllocationHint() helper
- Check for both current and legacy PTY allocation hint variants
- Prevents duplication when messages already contain legacy hints
