docs(tess): remediate M5 qualification findings

docs/tess/THREAT-MODEL.md

@@ -33,14 +33,18 @@ Trust boundaries: Discord→plugin, CLI→gateway, plugin→gateway service iden
 6. Every externally caused operation is replay-safe and correlated.
 7. Provider capability absence is a denial, not an invitation to shell around it.
 
-## Existing Findings That Block Tess
+## Closed Prerequisite Findings
 
-- Command executor lacks server-side enforcement for declared scopes.
-- Session list/reuse/destroy surfaces are not owner-filtered consistently.
-- MCP schemas accept caller-supplied user identity.
-- Discord plugin lacks a complete authenticated service ingress and user/channel allowlists.
-- Chat/tool persistence lacks mandatory redaction.
-- Sessions/pending Discord output are in-memory and not restart-safe.
-- Session GC currently performs globally scoped promotion.
+The original M1 findings below are closed by landed controls and retained for audit traceability.
 
-These are tracked as M1 security prerequisites and must pass independent security review before Tess ingress is enabled.
+| Former finding                              | Closed evidence                                                                                                                                                                                                    |
+| ------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
+| Command scope/role enforcement              | `apps/gateway/src/commands/command-authorization.service.ts` and its authorization tests enforce the server-side approval boundary.                                                                                |
+| Cross-owner session access                  | Gateway session ownership tests cover server-derived owner and tenant scope.                                                                                                                                       |
+| Caller-controlled MCP identity              | MCP tools derive actor and tenant from authenticated gateway context.                                                                                                                                              |
+| Missing Discord ingress allowlists          | `apps/gateway/src/plugin/plugin.module.ts` requires the guild, channel, and user allowlist environment values; `apps/gateway/src/plugin/discord-ingress.security.spec.ts` exercises denial and configured ingress. |
+| Missing redaction before persistence/egress | Gateway and log redaction coverage verifies sensitive content is classified before durable storage or channel delivery.                                                                                            |
+| In-memory-only restart safety               | `packages/agent/src/durable-session.test.ts` reconstructs durable identity, inbox/outbox, checkpoints, and handoffs after simulated restart.                                                                       |
+| Globally scoped session GC                  | `apps/gateway/src/gc/session-gc.service.spec.ts` verifies session-only collection and the absence of automatic global collection entry points.                                                                     |
+
+These controls remain subject to the runtime's independent review and release qualification gates.