apply_patch embeds deleted binary contents in session metadata

Description

Deleting a binary or very large file with apply_patch decodes the entire file as UTF-8 and generates a full unified diff. The diff is stored in both the tool result and per-file metadata, so deleting one large archive can add hundreds of megabytes to opencode.db and terminate the Desktop sidecar.

The delete operation only needs the path; binary and oversized file contents should be omitted from metadata.

Plugins

None required.

OpenCode version

1.18.16

Steps to reproduce

1. Create a large ZIP file in a project.
2. Delete it through an apply_patch *** Delete File operation.
3. Inspect the resulting tool part/event in opencode.db.
4. Observe that the deleted bytes are decoded into a full diff in both metadata.diff and metadata.files[].patch.

With a roughly 295 MB archive, the stored tool part and event were about 619 MB each and the Desktop sidecar exited immediately afterward.

Screenshot and/or share link

Not included because the affected session contains local file metadata. A focused regression test is available with the fix.

Operating System

Windows 11 x64

Terminal

OpenCode Desktop