checks/health: its marker lists the predefined keys, the modules' templates and health-undeclared it reads (issue 1936)

ReadTreeManifest reads predefined.json and each templated module's templates (WithTemplatesFrom), and the test reads
the root's health-undeclared through Kept: none was listed, so a change to them reused a stale verdict. No other
marker's package reads manifests through ReadTreeManifest beyond what it lists. Review finding F1 on ba49a7f0.

checks/health/reads-outside

@@ -1,5 +1,10 @@
 # What these tests read outside their package, as paths from the repository's root (a glob, or a directory read whole;
 # ? before a path whose absence is read). mesh-build-go hashes them into the package's digest, so its verdict is kept
 # until one of them changes (issue 1936). An empty list, or a line matching nothing, keeps nothing.
-# every manifest.
+# every manifest through mesh-sdk's ReadTreeManifest: the root's predefined keys and each templated module's
+# templates (files/ by default, or the directory its manifest names); and the root's kept count of undeclared ports.
 modules/*/module.json
+predefined.json
+modules/*/files
+modules/*/templates
+health-undeclared