test: pin current tool-eval, guardrail, and truncation behavior ahead of background-jobs work
T0 characterization safety net per plans/background-jobs-design.md §9.3: 43 tests
pinning handle_collect/check/cancel/spawn, the pending-agents guardrail (incl.
ForceTerminate + counter resets), eval_tool_calls partition/re-sort/soft-fail/
loop-alert/truncation, truncate_if_needed's UTF-8 boundary edge, ToolCall::eval
prefix routing, merge_tool_results shape, and cancel_recursive recursion.
Known-buggy behaviors deliberately pinned for visible later diffs: handle_check
consumes finished handles, guardrail ignores finished-but-uncollected agents,
mid-char truncation returns the full string with marker prepended.
Not covered (findings): empty-after-dedup bail is unreachable from non-empty
input; run_child_agent needs a mock LLM client (none exists) — manual case;
over-threshold summarization pinned via deterministic unknown-model failure.
Dark-Alex-17
bfc3b7bfea