feat(shell): enable PTY by default and various enhancements

### Shell & Interactive Terminal Improvements
- PTY shell is now enabled by default instead of disabled
- Improved shell output rendering, process termination, and added fallback warning
- Background commands now properly capture subprocess PIDs on non-Windows

### Coding Plan Improvements
- Simplified auth message, added /model tip, improved system info display
- Reordered model list to prioritize glm-5, kimi-k2.5, MiniMax-M2.5
- Model selection is now preserved when updating if the model still exists

### Other Changes
- Added shared symlink utility; debug logs now have latest alias
- Unknown settings warnings go to debug log instead of user-facing warnings
- Fixed subagent confirmation state detection
- Removed debug UI from AgentCreationWizard

Co-authored-by: Qwen-Coder <qwen-coder@alibabacloud.com>

packages/cli/src/config/settingsSchema.ts

@@ -822,9 +822,9 @@ const SETTINGS_SCHEMA = {
             label: 'Interactive Shell (PTY)',
             category: 'Tools',
             requiresRestart: true,
-            default: false,
+            default: true,
             description:
-              'Use node-pty for an interactive shell experience. Fallback to child_process still applies.',
+              'Use node-pty for an interactive shell experience. Falls back to child_process if PTY is unavailable.',
             showInDialog: true,
           },
           pager: {