feat(settings): accept VSCode remote prefix for SSH-tunneled hosts

[DavidBabel]

Summary

Every 'Open in VSCode' file link now uses the official VSCode URL format and honors a new customizable remote prefix:

• Fix: Append '::1?windowId=_blank' to all editor file links (defaults to ':1:1'), which allows opening wsl / ssh folders
  Prevent fails on openning files on SSH connection, and recommended in VSCode guidelines.
• Add 'editor.vscodeRemotePrefix' setting (empty by default), exposed in Settings > Advanced as a composite input rendered as vscode://[prefix]/path/to/file with monospace literals

The setting only appear if the option Show "Open in VSCode" links is activated :

• When set and the server is not WSL, links are built as vscode:/// instead of vscode://file/... ; applied to tool-call links, diff rows and the workspace folder link
• WSL auto-detection keeps priority, so local/WSL default behavior is unchanged

Why ?

The "open is VSCode" feature is really great. It works with Windows and local WSL. But VSCode is able of more, you can now open any repository with a simple SSH tunnel connexion. And since you can use openfox in browser, you can run it from a remote machine too.
The idea of this PR is to council this 2 capabilites by providing an SSH configurable prefix in the vscode:// links

AI-Enhanced Development

Tell what models helped shape this PR:

AI Models: Qwen 3.8 Flash Next 110b Q4XL

Cache Impact

Does this PR affect anything cached — system prompts, tool definitions, skills, or other context?

• No