Adds fs.write-file / fs.write-bytes behind a new fs.write:<path> capability (high risk; resolved to the real path, a missing file through its real directory, so a link cannot reach outside the grant; writing doesn't imply reading), and workspace.project.write-file(path, text) behind project.write (medium risk; stays inside the root and creates missing directories).
Writes go through the editor's save path: atomic, keeping the file's encoding and BOM (new files are UTF-8), capped at 16 MiB, and refused while an editor holds unsaved changes for the file. Both capabilities need engines.openidea ^1.3. Tested through the real component (misbehave fixture) and the SDK mock.
Closes#1823Closes#1824
Co-authored-by: chaoes <[email protected]>