Stop the runaway scan from telling Captains to rotate crew threads that hold a PR (GST-2226) (#4250)

* Stop the runaway scan from telling Captains to rotate crew threads that hold a PR (GST-2226)

Only a thread marked standing rotates, and never while it holds an open PR or its PR list is missing; a crew thread gets one CHECK_IN past 1B own tokens (R70 as amended, R91).

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* Trim the runaway-stopper wording so it fits the skill context budget with #4244

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

* Reword the runaway-scan changelog entry so it passes the prose check

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

---------

Co-authored-by: capy-ai[bot] <230910855+capy-ai[bot]@users.noreply.github.com>

docs/skills.md

@@ -969,7 +969,8 @@ sets the defaults that keep it from coming back.
 - **Detect.** One program fetches each crew thread (`tools.thread.get`, with its transcript) to files, then
   `gstack-runaway scan --dir <dir>` prints a `RUNAWAY:` line per thread and a `FLAG:` line per limit crossed:
   own tokens past 500M or active past 3 days (rotate, for a standing thread that wakes on every event; a crew
-  thread keeps its PR until it merges or closes and checks in with its Captain once past 1B), a subagent past 100M (stop), empty wakes past 25% of the
+  thread keeps its PR until it merges or closes and checks in with its Captain once past 1B, and no thread holding an
+  open PR rotates), a subagent past 100M (stop), empty wakes past 25% of the
   last 40 turns (warm-wait check-ins are left out), and review rounds past 2 per PR. Captains are reported, never rotated.
 - **Stop.** A live subagent past 100M is stopped with its reason. A standing thread is rotated at a clean point through
   a handoff file and a successor brief (`runaway-stopper/templates/`), then archived by its own Captain once none of
@@ -979,7 +980,8 @@ sets the defaults that keep it from coming back.
   PR head (metering its own row with a 100M default cap, `BUDGET_DEFAULT_CAP:`), two review rounds, and a fresh
   thread per automation run.
 
-Scanning FOUN-4, FOUN-14 and FOUN-71 as read on 2026-11-03 (excerpt):
+Scanning FOUN-4, FOUN-14 and FOUN-71 as read on 2026-11-03, before R70's 2026-11-09 amendment (today only a thread
+marked standing gets `ROTATE`, a crew thread past 1B gets `CHECK_IN`, and a thread holding an open PR never rotates) (excerpt):
 
 ```
 RUNAWAY: thread=FOUN-4 verdict=ROTATE own=4.04B(upper) total=6.90B credits=2299398 age_days=13.1 active=yes ...