Two fixes for autoCapture reliability:
1. Strip injected memory context before capture filtering
- autoRecall prepends <relevant-memories> to user messages
- This was causing shouldCapture() to skip all user messages
- Now strips the context before evaluating capture criteria
2. Process only current turn instead of full history
- Previously scanned all messages and picked arbitrary 3
- In long sessions (100+ messages), recent content was missed
- Now captures only last user + last assistant message
- Previous turns were already captured when they occurred
These fixes ensure that autoCapture reliably stores each conversation
turn as it happens, rather than missing recent exchanges.
