Writes bytes to one file at a path the session resolves: how a surface
with no reach into a filesystem (a browser) delivers a file. The backend
does the writing.
Parameters
filePath: string
The destination path (absolute or cwd-relative).
bytes: Buffer
The content to write.
Returns Promise<void>
Throws
When the backend refused the write, or has no files.
Writes bytes to one file at a path the session resolves: how a surface with no reach into a filesystem (a browser) delivers a file. The backend does the writing.