fix(cli): prevent auto compaction loop and prune messages until valid

[uinstinct]

Description

Prevent infinite looping when auto compaction happens.
Also prune messages when auto compaction fails and context length is invalid/exceeding, until chat history is within context length.

resolves CON-4681
resolves CON-4455

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Checklist

• [] I've read the contributing guide
• [] The relevant docs, if any, have been updated or created
• [] The relevant tests, if any, have been updated or created

Screen recording or screenshot

(both having context length set as 300 in the config.yaml)

before.mp4

after.mp4

Tests

[ What tests were added or updated to ensure the changes work as expected? ]

[uinstinct]

Was looking at countChatHistoryItemTokens. Why do we not count the systemMessage and the tool call results?

From the ticket, it looks like there is some counting mistake that is happening because before getting the 500 error from the server, we should have received our internal Context length validation failed error in the tui.

[cubic-dev-ai]

No issues found across 2 files