fix: fix auto_compact truncating latest conversation content

[Zheisenbergy]

Related Issue

Closes #109

Problem Description

In the auto_compact function of s06_context_compact.py, the code uses [:80000] to intercept the beginning of the string.
Since the messages list is stored in chronological order (oldest first, newest last), this causes the latest tool execution results and task status to be discarded directly.
The generated summary loses current progress, making the agent "amnesiac" after compression.

Fix

Changed string interception from start to end:

# Before
conversation_text = json.dumps(messages, default=str)[:80000]
# After
conversation_text = json.dumps(messages, default=str)[-80000:]

[vercel]

@Zheisenbergy is attempting to deploy a commit to the crazyboym's projects Team on Vercel.

A member of the Team first needs to authorize it.