Compacted tool outputs and attachments not cleared from storage, causing memory growth #7421

Problem

When compaction prunes old tool outputs (in packages/opencode/src/session/compaction.ts), only the time.compacted timestamp is being set. The actual output string (often containing large file contents) and attachments array (base64 images/PDFs from the Read tool) remain in the storage JSON files indefinitely.

This causes storage files to grow unbounded, contributing to memory issues during extended use.

Expected Behavior

When prune() marks tool parts as compacted, it should also clear the output string and attachments array to free memory.

Actual Behavior

Only time.compacted is set; large output strings and attachment data persist indefinitely.

Related

• Part of the memory leak issues reported in Memory stays unbounded: ACP session map + compacted tool outputs #4315, opencode eating 70gb of memory? #5363