feat: implement update-service v1 migration and enrollment flow

- added /update/enroll endpoint and enrollment logic
- migrated update client to v1 api endpoints and bearer auth
- implemented remote status reporting in backend and scripts
- updated requirements and project status

docs/architecture/openapi/schemas/manifest.yaml

@@ -0,0 +1,24 @@
+type: object
+required:
+  - version
+  - artifact_url
+  - sha256
+properties:
+  version:
+    type: string
+    description: SemVer string (e.g., 1.2.3)
+    pattern: '^[0-9]+\.[0-9]+\.[0-9]+(-[0-9A-Za-z.-]+)?(\+[0-9A-Za-z.-]+)?$'
+    example: 1.2.3
+  artifact_url:
+    type: string
+    format: uri
+    example: https://update.wlkns.org/v1/projects/demo/releases/1.2.3/artifact
+  sha256:
+    type: string
+    description: Hex-encoded SHA256
+    example: 9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08
+  sig_url:
+    type: string
+    format: uri
+    nullable: true
+    example: https://update.wlkns.org/v1/projects/demo/releases/1.2.3/signature