fix(BetaToolRunner): include current turn in compaction scope

[gn00295120]

Summary

Fixes #892 — BetaToolRunner compaction only summarizes older messages, missing the token-heavy current turn.

When auto-compaction fires, #checkAndCompact() was called BEFORE the current assistant message and tool results were pushed to this.#state.params.messages. This meant the compaction summary only covered older history, leaving the most token-heavy content (tool results from the current turn) out of the summary — defeating the purpose of compaction.

Also fixes #886 as a side effect — the push/break logic is no longer gated on the compaction result, preventing the infinite loop and message loss issues.

Changes

src/lib/tools/BetaToolRunner.ts:

• Moved assistant message push and tool response generation BEFORE #checkAndCompact()
• Compaction now only runs when tool results exist (no need to compact on the final text response)
• The if (!isCompacted) guard is removed — push and tool response always execute

tests/lib/tools/ToolRunner.test.ts:

• Added test verifying compaction receives tool_result messages in its scope

Before/After

Before: Compaction fires → summarizes [user_msg] only → tool_result (90K tokens) stays in context
After: Push assistant + tool_result → compaction fires → summarizes [user_msg, assistant, tool_result] → full context reduction

Test plan

• All 23 existing tests pass unchanged
• New compaction scope test verifies tool_result is present in compaction messages
• max_iterations test still works correctly (5 messages as expected)
• generateToolResponse() caching still works
• Streaming and non-streaming modes both work

[Copilot]

Pull request overview

This PR fixes BetaToolRunner auto-compaction so that summarization includes the current turn’s assistant tool_use and subsequent tool_result messages, preventing token-heavy tool output from being left un-compacted. It also removes the prior compaction-gated push/break behavior that could cause looping and message loss.

Changes:

• Reordered the tool loop to push the current assistant message and tool results before invoking #checkAndCompact().
• Runs compaction only after tool results are generated (i.e., when a tool_result message is appended).
• Added a unit test asserting the compaction request includes tool_result messages from the current turn.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/lib/tools/BetaToolRunner.ts	Ensures compaction scope includes the current assistant + tool result messages by moving history updates ahead of compaction.
tests/lib/tools/ToolRunner.test.ts	Adds coverage to verify compaction receives current-turn tool_result messages (regression test for #892).

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