huskies: merge 645_bug_agent_runtime_panics_with_output_write_bytes_is_ok_assertion_marking_stories_falsely_blocked

.huskies/specs/tech/STATE_MACHINE.md

@@ -181,6 +181,25 @@ The mergemaster agent only runs against stories in `4_merge/`. It:
 4. On failure beyond the retry budget, writes `merge_failure` and blocks the
    story (auto-assign then skips it).
 
+### Agent terminated with committed work (bug 645 recovery path)
+
+When a coder agent terminates abnormally (e.g. the Claude Code CLI's
+`output.write(&bytes).is_ok()` PTY write assertion fires mid-session), the
+server-owned completion path detects the crash and checks for surviving work:
+
+1. If the worktree is dirty but has commits ahead of master, reset the
+   uncommitted files (`git checkout . && git clean -fd`) and run gates
+   against the committed code.
+2. If gates still fail but `git log master..HEAD` shows commits and
+   `cargo check` passes, **advance to QA** instead of entering the
+   retry/block path.  This is the "work survived" check, implemented in
+   `server/src/agents/pool/pipeline/advance.rs`.
+3. Agents that die WITHOUT committed work (no commits ahead of master)
+   still follow the existing retry → block path unchanged.
+
+This prevents false-positive blocking of stories where the agent completed
+meaningful work before crashing.
+
 ### Watchdog (current production)
 
 The "watchdog" at `server/src/agents/pool/auto_assign/watchdog.rs` runs every