test(compaction): failing tests for missing headroom when limit.input is set

[lightsofapollo]

Relates to #10634

adds 3 failing tests showing that isOverflow() doesn't reserve any headroom when limit.input is set, unlike the context - output fallback path.

basically if you have a model with limit.input = 200K and you've used 198K tokens, isOverflow says you're fine. next turn overflows.

without limit.input, same scenario correctly triggers compaction because it uses context - output (168K).

the diff between the two paths is exactly 32K — the output budget that's not being subtracted.

was hitting this with claude models in our tui project and traced it to line 37 in compaction.ts. saw #6875 and #12924 are both trying to fix this — these tests should pass once either lands.

related: #10634 #8089 #11086

[github-actions]

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[github-actions]

The following comment was made by an LLM, it may be inaccurate:

Perfect! I found the related PRs. Here are the potential duplicates/related PRs:

Related PRs Found

1. PR fix(core): ensure compaction is more reliable, add reserve token buffer to ensure that input window has enough room to compact #12924 - fix(core): ensure compaction is more reliable, add reserve token buffer to ensure that context window has enough room to compact

   • This is explicitly mentioned in the PR description as one of the fixes that should make these tests pass

2. PR feat(compaction): Handle when models have input limit #6875 - feat(compaction): Handle when models have input limit

   • Also explicitly mentioned in the PR description as attempting to fix the same issue

These two PRs are directly addressing the root cause that PR #13034 is testing. The current PR adds failing tests that verify the bug exists, and PRs #6875 and #12924 are the actual fix implementations for the isOverflow() function's handling of limit.input and output budget headroom.

[rekram1-node]

ill just absorb into my branch since im working on this stuff

[lightsofapollo]

@rekram1-node Ty!