Accept a plain-language go-ahead, announced and revision-bound

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PPQ14L3LikyefCMFBqEbKE

docs/Architecture.md

@@ -396,6 +396,12 @@ that works in every state: `status`, `stop`, `abandon`, `approve [rev-N]`, `go`
   drawn from the work item's context, and is never read as approval, rejection or
   a command. How a question is recognised (explicit marker or classification) is
   an open question (Q); a misread must default to asking, never to acting.
+- **One exception: a plain-language go-ahead.** A conversational reply to a
+  restatement ("yep, that's it") may be taken as `go` (D1), because a wrong reading
+  costs only time: the work is contained and ends in a PR. The agent says so before
+  acting ("taking that as a go-ahead on rev-2; starting"), and the reading is bound
+  to the revision up when the reply arrived (L3). Approvals of anything else (ops
+  step sequences, class-3 actions) still need an explicit `approve`.
 - **Everything the operator says is recorded** in the work item's transcript
   (L7), even when no action follows.
 
@@ -811,7 +817,8 @@ request to mean, how it fits the architecture, and its first step. Then:
   on the operator, so the agent may work on something else; when it expires the
   item is ready.
 - **Anything else** (a feature, a change, a question) waits for the operator's
-  go-ahead after the restatement; the conversation is where the design is agreed.
+  go-ahead after the restatement: `go`, or a plain-language yes, which the agent
+  announces it is acting on (L5). The conversation is where the design is agreed.
 - **Talk first when:** the issue is labelled `discuss`; the agent finds the report
   unclear (it asks its questions instead of restating); or it can't reproduce a
   bug. It never fixes a bug it couldn't see.