Make the ship queue fetch the latest main before it checks a pull request (GST-2232) (#4256)

* Make ship-queue ready fetch the base before it checks the receipt (GST-2232)

ready read origin/<base> as the clone last fetched it, so a lane a few landings behind measured the PR from an older merge base and refused a good receipt with a false RECEIPT_INVALID field=review_exclude. ready now fetches the base first and refuses QUEUE_BASE_UNFETCHED when it cannot; the stamp path of land refuses the same way instead of ignoring a failed fetch.

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

* Regenerate the doctor component list for the new queue refusal code (GST-2232)

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

* Keep the new ready test off the Windows-safe set and say which land path uses the new refusal (GST-2232)

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/ship-policy.md

@@ -732,7 +732,13 @@ slot. The queue enforces this at every step from the PR body alone:
   `REVIEW_TARGETED:` line) when a targeted class the head needs has no done
   targeted pass in the receipt, and `QUEUE_RECEIPT_EXCEPTION_INVALID` when an
   owner exception it records does not stand ([the ship receipt](#ship-receipt)).
-  There is no flag around it.
+  There is no flag around it. Before any of these checks, `ready` fetches
+  `origin/<base>` and reads the policy and every receipt field against that
+  fresh ref, so a lane clone whose base is behind the remote never turns a good
+  receipt into `RECEIPT_INVALID` (GST-2232); a failed fetch refuses with
+  `QUEUE_BASE_UNFETCHED` before anything is compared. The stamp path of `land`
+  refuses the same way; `land --pin` (`merge: direct`) refuses a failed fetch
+  with `QUEUE_NOT_READY`, as it already did.
 - `train build` refuses a pin whose PR has no current receipt with the same
   codes, naming the PR, before anything is written, pushed or dispatched,
   `--dry-run` included.
@@ -1546,7 +1552,9 @@ same one (a mixed set makes it `VERIFY: dirty`). `gstack-ship-receipt write
 --review-exclude <d>`, with that digest, records `review_exclude` (source, patterns, counts, the gate-tagged kept
 paths and three hashes). The `digest` hashes the declared patterns and the
 excluded and kept lists; `source` is provenance only. Write, carry and the queue
-each recompute the digest at the current base and compare it, so a base merge
+each recompute the digest at the current base and compare it (the queue fetches
+that base first), over the PR's own files: the diff from the head's merge base
+with that base, never a two-dot diff against the base tip, so a base merge
 or a moved base that leaves the patterns and the lists unchanged still carries
 and binds. A different digest means the digest write was given (or the receipt recorded) names another selection than the head has now:
 write refuses with `RECEIPT_INVALID field=review_exclude`, carry with

docs/troubleshooting.md

@@ -5490,6 +5490,20 @@ the same `train land` command; it adopts its own journaled stamp commit. For an
 unreadable land lock, rerun the same `land` command once origin answers; it
 resumes its own lock.
 
+<a id="queue-base-unfetched"></a>
+### `QUEUE_BASE_UNFETCHED`
+
+**Meaning.** `gstack-ship-queue ready` (or the stamp path of `land`) could not
+fetch `origin/<base>`, so it stopped before reading the policy or comparing
+any receipt field. Both compare the receipt's recorded selection, depth and
+targeted classes with what the current base gives the head; a local
+`origin/<base>` a few landings old measures the PR from an older merge base,
+pulls in files of PRs that already landed, and reports a false
+`RECEIPT_INVALID field=review_exclude` (GST-2232). Nothing was written.
+
+**Fix.** Make `git fetch origin <base>` work in this clone (network, remote
+URL, credentials), then rerun the same command.
+
 <a id="queue-proof-missing"></a>
 ### `QUEUE_PROOF_MISSING`