meta-forgefirm: the image manifest (/etc/forgefirm-manifest.json)

Every image records the identity of its build inputs. forgefirm-manifest.bbclass
gives a component recipe a per-file source fingerprint (git ls-tree blob ids,
submodules recursed; file:// sources hashed with git hash-object); the kernel
and glowforge.ko publish theirs through do_deploy because kernel-module-split
leaves the module recipe's main package empty. forgefirm-image-manifest.bbclass
assembles the entries with the platform identity - machine, modules directory,
device tree hashes, layer content hashes (meta-forgefirm and the meta-openglow
layers by content, the kas-managed layers by revision) - into
/etc/forgefirm-manifest.json and deploys a copy next to the image. Layer
revisions and dirty flags stay outside the identity, so a rebuild from an
unchanged tree keeps its content hash and the release and dev images of one
build share it. The acceptance tool and the release gate read this file.

meta-forgefirm/recipes-devtools/python/python3-gfutilities_%.bbappend

@@ -0,0 +1,3 @@
+# ForgeFIRM image manifest: source fingerprint of the cloud-mode service
+# layer (forgefirm-manifest.bbclass in this layer).
+inherit forgefirm-manifest