claim(cfold): M1 canonical custom folder migration

machine-docs/JOURNAL-cfold.md

@@ -56,4 +56,43 @@ Post-move grep state:
 - the pre-migration inventory in `BACKLOG-cfold.md` is intentionally unchanged because it is the M1
   baseline record the Adversary will compare against.
 
-Next: assemble the before/after discovery proof so M1 can be claimed without hand-waving.
+## 2026-06-12 — M1 coverage proof assembled
+
+Verification commands + observed outputs:
+
+```bash
+$ git ls-files "tests/*/custom/test_*.py" | wc -l
+64
+
+$ git ls-files "tests/*/functional/*" "tests/*/playwright/*"
+# no output
+
+$ for recipe in bluesky-pds cryptpad custom-html custom-html-tiny discourse drone ghost hedgedoc immich keycloak lasuite-docs lasuite-drive lasuite-meet mailu matrix-synapse mattermost-lts mumble n8n plausible uptime-kuma; do count=$(git ls-files "tests/$recipe/custom/test_*.py" | wc -l); printf "%s %s\n" "$recipe" "$count"; done
+bluesky-pds 4
+cryptpad 4
+custom-html 4
+custom-html-tiny 1
+discourse 3
+drone 1
+ghost 4
+hedgedoc 2
+immich 3
+keycloak 3
+lasuite-docs 5
+lasuite-drive 3
+lasuite-meet 3
+mailu 3
+matrix-synapse 3
+mattermost-lts 3
+mumble 5
+n8n 4
+plausible 2
+uptime-kuma 4
+
+$ nix shell nixpkgs#python311Packages.pytest -c pytest tests/unit/test_discovery.py tests/unit/test_discovery_phase2.py tests/unit/test_manifest.py -q
+..................
+18 passed in 0.14s
+```
+
+Conclusion: the migrated tree still contains the exact same 64 custom test files with the same
+per-recipe cardinality as the pre-cfold baseline in `BACKLOG-cfold.md`; only the folder paths changed.