[Golden-Pigeon]

Fixes #21.

Original problem

On a Windows client, opening a mirrored remote workspace resolved the remote POSIX path with the client platform path implementation. /home/ubuntu became C:\home\ubuntu, was sent as remotePath to the remote agent, and file list/stat/read failed with not found: C:\home\ubuntu.

Change

• Split local anchor resolution (platform path) from remote workspace resolution (POSIX path) in a pure resolver used by the workspace-files adapter.
• Convert the workspace-relative path to / separators before joining the remote root.
• Added 9 path tests covering Windows anchors, relative paths, the workspace root, remote absolute paths outside the root, and escape rejection.

Fixed during this change

• None.

Resolved

• Windows clients can list/stat/read mirrored workspace files under POSIX remote roots.
• The adapter no longer sends a Windows-resolved path to the remote agent.

Unresolved

• None within the scope of Windows client: remote file list/stat/read resolves POSIX paths to C:\home\... and fails #21.

Testing

• pnpm --filter dsh-remote-local-plugin test (126/126)
• pnpm --filter dsh-remote-local-plugin typecheck
• pnpm --filter dsh-remote-local-plugin build
• Real Windows host: ran the compiled resolver with the Windows node:path; /home/ubuntu stays /home/ubuntu, the local anchor uses backslashes, and all cases pass.