From 893172f57d8a0fdab2f3750f89d0f766ab821839 Mon Sep 17 00:00:00 2001
From: l0ng-ai <24760907+l0ng-ai@users.noreply.github.com>
Date: Mon, 7 Sep 2026 11:24:37 +0800
Subject: [PATCH] fix(control): raise the dialect to v9 rather than walk it
 back to 7
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Reverting the projects layer took CONTROL_VERSION back to 7 with the
verbs it had been raised for. The dialect that number describes is
correct — this build speaks v7's messages again, one for one — but the
number is not, because v8 is already deployed.

A version that moves backwards stops being an identity. A 7 on the wire
would mean "before projects" or "after them" depending on which build
sent it, and the handshake has nothing but the number to tell those
apart: a v8 peer would read our 7 as an older server it may keep
talking to, and every project verb it pushed would fail to decode and
drop the link.

v9 is a number no peer has seen, so a v8 peer is turned away at the
handshake instead. Nothing else changes; every other reference to the
constant is relative to it.

Claude-Session: https://claude.ai/code/session_015q6HRem76HYy33T39bp34c
---
 crates/tty7-core/src/daemon/control.rs | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/crates/tty7-core/src/daemon/control.rs b/crates/tty7-core/src/daemon/control.rs
index 4172676c..e2ec9f0a 100644
--- a/crates/tty7-core/src/daemon/control.rs
+++ b/crates/tty7-core/src/daemon/control.rs
@@ -34,7 +34,16 @@ use super::protocol::{MAX_FRAME, read_frame, write_frame};
 /// refusing to kill a server it has nothing to replace with — can be exercised
 /// against the v6 servers already deployed. A number is the only way to reach
 /// that path, and a mismatch nobody can reproduce is a mismatch nobody can fix.
-pub const CONTROL_VERSION: u32 = 7;
+///
+/// v8 added the project verbs; v9 takes them back out. The dialect this build
+/// speaks is v7's again, message for message, but the number does not go back
+/// to 7 with it: v8 is deployed, and a number that moves backwards stops being
+/// an identity and becomes a coincidence. A 7 on the wire would then mean
+/// either "before projects" or "after them" depending on which build put it
+/// there, and the handshake — which has nothing but the number — cannot tell
+/// the two apart. A v8 peer meeting this one must be turned away, and only a
+/// number it has never seen does that.
+pub const CONTROL_VERSION: u32 = 9;
 
 const DIALECT_MARKER: &str = "speaks control v";