fix(ci): give the release-candidate web check the history addedAt is derived from

The exact-head release-candidate run on 2ca42e9 failed in "Verify exact
candidate web surface": `check:facts` reported the committed
`facts.generated.ts` as stale with every model's `addedAt` collapsed to
2026-09-20. The web job checked out at the default depth 1, and
`web/scripts/facts-lib.mjs` derives `addedAt` from the commit on which
each model id first appeared in the declaration paths, so a shallow
checkout can only ever answer "today". web.yml and ci.yml already pin
`fetch-depth: 0` for exactly this reason; the last green candidate run
(run 87, 2026-09-14) predates the 2026-09-19 facts-script changes, so
this has been broken on main since then and is not specific to this
branch.

Validation: workflow YAML parses; the same checkout setting is what the
green web.yml check job uses. Judged by re-dispatching
release-candidate.yml on this head.

Co-Authored-By: Claude Fable 5.1 <[email protected]>
Claude-Session: https://claude.ai/code/session_0134iUMxmGuXiG1LzPgfZVnv

.github/workflows/release-candidate.yml

@@ -88,6 +88,13 @@ jobs:
       # resolve already proved expected_sha equals GITHUB_SHA. Do not
       # interpolate that SHA into checkout or the npm cache key.
       - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7
+        with:
+          # `check:facts` derives each model's `addedAt` from the commit date
+          # on which its id first appeared in the model declaration paths
+          # (web/scripts/facts-lib.mjs). A shallow checkout collapses every
+          # date to the tip commit and the committed facts always read as
+          # stale; web.yml and ci.yml pin depth 0 for the same reason.
+          fetch-depth: 0
       - uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
         with:
           node-version: 22