feat: implement release authoring, so the changelog can be written

The public site has a Releases page and a footer link to the latest release,
and both were empty — the read side has existed since the public surface
landed, but nothing could ever create a row. The seven release operations were
in the contract with no implementation, so the changelog was a page that could
only ever be blank.

The release model is not a blob of prose. It splits into six markdown sections
because a release note answers fixed questions — why, what, what changes for a
reader, what it leaves in the code, how it was verified, what is still missing
— and a single text column cannot say which of those went unanswered.

Publishing is the only thing that makes a release public: the public query
filters on `workflow_status = 'PUBLISHED'` and nothing else. So publish is
where the contract's required fields are actually enforced. Saving stays
permissive — a draft you cannot save until it is complete is a draft you cannot
write — and the two demands are deliberately different.

`version_label` is NOT NULL UNIQUE but a draft has no version yet, so creation
writes a placeholder derived from the row id and publication refuses to ship
one. Relaxing the column instead would open a window where a published release
is publicly visible with no version at all.

A published release cannot be deleted, only archived: a public changelog entry
that vanishes leaves everyone who linked it with no way to learn what happened.

Also registers `adapter-outbound-objectstorage` as an app-bootstrap runtime
member. It was added as a dependency when asset upload was fixed but never
registered, and `verifyRuntimeModuleMembership` had not been run since.

docs/registries/error-codes.yaml

@@ -1363,4 +1363,43 @@ errors:
     log_level: INFO
     runbook_link: null
     compatibility_impact: additive
+    required_test: ManagementErrorRegistryTest
+  # source: studio-management-v1.yaml ApiError.code — RELEASE_NOT_FOUND (ManagementError.RELEASE_NOT_FOUND)
+  - code: RELEASE_NOT_FOUND
+    category: NOT_FOUND
+    http_status: 404
+    retryable: false
+    retry_after_seconds: null
+    owner_branch: feature-techlog-management-v1
+    owner_layer: application
+    client_safe_message: "요청한 릴리즈를 찾을 수 없습니다"
+    log_level: INFO
+    runbook_link: null
+    compatibility_impact: additive
+    required_test: ManagementErrorRegistryTest
+  # source: studio-management-v1.yaml ApiError.code — RELEASE_VERSION_TAKEN (ManagementError.RELEASE_VERSION_TAKEN)
+  - code: RELEASE_VERSION_TAKEN
+    category: CONFLICT
+    http_status: 409
+    retryable: false
+    retry_after_seconds: null
+    owner_branch: feature-techlog-management-v1
+    owner_layer: application
+    client_safe_message: "같은 버전의 릴리즈가 이미 있습니다"
+    log_level: INFO
+    runbook_link: null
+    compatibility_impact: additive
+    required_test: ManagementErrorRegistryTest
+  # source: studio-management-v1.yaml ApiError.code — RELEASE_NOT_PUBLISHABLE (ManagementError.RELEASE_NOT_PUBLISHABLE)
+  - code: RELEASE_NOT_PUBLISHABLE
+    category: CONFLICT
+    http_status: 409
+    retryable: false
+    retry_after_seconds: null
+    owner_branch: feature-techlog-management-v1
+    owner_layer: application
+    client_safe_message: "지금 상태에서는 발행할 수 없습니다"
+    log_level: INFO
+    runbook_link: null
+    compatibility_impact: additive
     required_test: ManagementErrorRegistryTest