fix(gates): gate on the DEED grammar, per the template and standards#837 (#389)

## Why

The guard in `dogfood-gate.yml` counted `.a2ml` files only:

```
COUNT=$(find . -name '*.a2ml' -not -path './.git/*' | wc -l)
```

so a repo whose manifest is written in the current grammar is reported
as having none, and the
summary/compliance row is skipped by the same predicate (`if find .
-name '*.a2ml' ... | grep -q .`).
The validator itself has scanned both grammars for a while -- the
caller's predicate is the bug.

## Authority

- `rsr-template-repo/.github/workflows/deed-validate.yml` (the mint
source) is what this wording is
copied from, byte for byte, including `-type f`-free `find` and the
dual-accept stance.
- `standards#837` — "DEED conversion campaign", campaign step 4: *"flip
... RSR gates from `.a2ml`
presence to `.deed` presence alongside". Gate predicates, not document
contents.
- `deed-ecosystem/README.adoc`: *"The DEED format name and `.deed`
extension are final, not A2ML."*

## Deliberately not done

- No `.a2ml` file is translated or renamed. #837 makes classification
into the four DEED forms and
per-family mapping specs a prerequisite for mass translation; that is
not this PR.
- No gate that *reads* a retained file is touched (`CLAIMS.a2ml`,
`.machine_readable/Debtfile.a2ml`,
`contractiles/INDEX.a2ml`); rewriting those would fail gates that
currently pass.
- No job-id or shell-var renames (`a2ml-validate`, `A2ML_COUNT`): they
are referenced from `needs:`
and `${{ needs.*.outputs }}`. The Checks-UI label is updated, as it has
no references.

_Estate-wide `.deed` gate convergence, 2026-09-21. Script:
`estate-audit/engine/deed_gate_migration.py`._

Author: hyperpolymath

.github/workflows/dogfood-gate.yml

@@ -30,7 +30,7 @@ jobs:
   # Job 1: A2ML manifest validation
   # ---------------------------------------------------------------------------
   a2ml-validate:
-    name: Validate A2ML manifests
+    name: Validate DEED manifests
     runs-on: ubuntu-latest
     timeout-minutes: 10
 
@@ -44,7 +44,7 @@ jobs:
           COUNT=$(find . -type f \( -name '*.a2ml' -o -name '*.deed' \) -not -path './.git/*' | wc -l)
           echo "count=$COUNT" >> "$GITHUB_OUTPUT"
           if [ "$COUNT" -eq 0 ]; then
-            echo "::warning::No .deed manifest files found. Every RSR repo should have 0-AI-MANIFEST.deed (.a2ml is legacy and no longer authored)"
+            echo "::warning::No .a2ml/.deed manifest files found. Every RSR repo should have a repo deed (<reponame>_chora.deed); legacy 0-AI-MANIFEST.a2ml accepted mid-migration — standards #837"
           fi
 
       - name: Validate A2ML manifests
@@ -57,7 +57,7 @@ jobs:
             cat <<'EOF' >> "$GITHUB_STEP_SUMMARY"
           ## A2ML Validation
 
-          :warning: **No manifest found.** Every RSR-compliant repo should have at least `0-AI-MANIFEST.deed`. (`.a2ml` still validates as legacy but is no longer authored.)
+          :warning: **No .a2ml/.deed manifest files found.** Every RSR-compliant repo should have a repo deed (`<reponame>_chora.deed`) at its root.
 
           Copy one from [rsr-template-repo](https://github.com/hyperpolymath/rsr-template-repo).
           EOF
@@ -103,7 +103,7 @@ jobs:
             cat <<'EOF' >> "$GITHUB_STEP_SUMMARY"
           ## K9 Contract Validation
 
-          :warning: **No K9 contract files found.** Repos with configuration files should have K9 contracts.
+          :warning: **No .a2ml/.deed manifest files found.** Every RSR-compliant repo should have a repo deed (`<reponame>_chora.deed`) at its root.
 
           Generate contracts with: `k9iser generate .`
           EOF