The "chatLanguageModels.json" file allows for the option to inherit from the default profile.

### Summary

Currently in multiple profiles, `chatLanguageModels.json` will not inherit the default settings.
When `chatLanguageModels.json` in a profile is empty, the settings in the default `chatLanguageModels.json` will not be inherited.

### Expected Behavior

- Either `chatLanguageModels.json` follows the same profile-inheritance model as
other user resources (a profile can choose "Use Default" and fall back to
`User\chatLanguageModels.json`),
- or the file is shared/merged across profiles by default.

### Actual Behavior

- Default profile reads `User\chatLanguageModels.json` → custom models appear. ✅
- Any non-default profile reads `User\profiles\\chatLanguageModels.json`
which is auto-created as `[]` → custom models disappear. ❌
- The Profiles manager UI does not list `chatLanguageModels.json` as a
toggleable/inheritable resource.

### Steps to Reproduce

1. Create a non-default profile (e.g. via `Profiles: Manage Profiles`).
2. In the Default profile, add a custom endpoint to
`C:\Users\\AppData\Roaming\Code\User\chatLanguageModels.json`.
3. Switch to the non-default profile, restart VSCode ,open Chat → "Switch Model".
4. Result: the custom models are missing.

Note: If you do not restart VSCode, the custom model will not be lost.

### Workarounds tried

- Copying the file content manually into each
`User\profiles\\chatLanguageModels.json` → works, but must be re-synced
manually on every change.

### Environment

版本: 1.131.0 (user setup)
提交: e4c7e7b1d6d060162f4aa7f8225271b67ce1df75
日期: 2026-07-28T10:51:25Z
Electron: 42.7.0
ElectronBuildId: 14710161
Chromium: 148.0.7778.280
Node.js: 24.18.0
V8: 14.8.178.38-electron.0
OS: Windows_NT x64 10.0.19045

Note: profile folders exist under
`AppData\Roaming\Code\User\profiles\\` each containing an empty
`chatLanguageModels.json` (`[]`)