chore(agent): phase roadmap from TODO.md, 5 phases

The four open items in TODO.md become an executable pipeline: 01 the
verification gate (host suites + sanitiser + both firmware envs, and the
hardware contract so no unit blocks on a board nobody is holding), 02 HTTPS
and wss:// with an identity the board generates itself into NVS, 03 session
takeover that always lands disarmed, 04 a responsive page whose safety
statements are pinned before they are trimmed, 05 the phone as a controller
(press-and-hold pad, soft keyboard, modifier latches over a new Q= frame).

TODO.md is cleared to its empty title; the items live in .agents/phases/ now.
AGENTS.md gains the five protocol rules and nothing else.

LLM-Generated: true

.gitignore

@@ -19,3 +19,5 @@ __pycache__/
 token
 *.capture
 *.log
+.agents/phase-sessions/
+.agents/pipeline.log