feat: require strict signed task authorization before approval consumption

Assistant: codex
Assistant-Model: gpt-6-astra
Assistant-Session: 01a140c4-354a-7823-8f0d-8f717397f786

workplans/SECRETS-WP-0013-task-scoped-openbao-execution.md

@@ -9,7 +9,7 @@ flavor: planning
 owner: codex
 topic_slug: netkingdom
 created: "2026-10-11"
-updated: "2026-10-11"
+updated: "2026-10-16"
 depends_on: []
 state_hub_workstream_id: "5e38aecc-85ca-5f55-94c6-9fbb08604819"
 ---
@@ -110,3 +110,17 @@ This is source preparation awaiting independent technical review/publication,
 not a formal owner assent, policy deployment or native execution milestone. T01
 remains progress; T03 and SECRETS-WP-0008-T06 remain open. Detailed limitations
 and retained failed test observations are in the source preparation receipt.
+
+
+2026-10-16 bounded source handoff preparation: `task_execution_handoff.py` uses
+the actual serving approval/mandatory signed Check path and retained detached
+artifacts to check exact descriptor/request/native approval/caller/lifetime joins,
+then performs one strict exact-response CAS only after Platform journal admission.
+It accepts no inbound boolean/mapping/authorizer callback and grants no native
+execution. Platform independently confirms durable consumption with the actual
+Approval provider client before native dispatch. Focused local HTTP/native Go
+producer-signature source checks cover altered joins/caller/grant, missing fields,
+coercion/idempotence, expiry, signer removal and replay refusal. No service binding
+propagation, policy gate flip, identity mapping admission or production trust/key
+change was made. Independent source integration/review and actual whole-provider
+proof remain required. T01/T03 and WP8-T06 retain their open native obligations.