The frontend half of bilateral gating. The nine discriminating rows
(G6a/b, G7a/b, G8a-e) and the full protocol gate are the checkpoint
after this.
**ONE ENUM, DERIVED ONCE.** `PanelFamily::{Unsupported, Legacy,
Mapped}` replaces the `panel_wire` bool, classified from
`session_protocol_version` at all four existing sites --- initial
attach and each reconnect --- and read by BOTH payload acceptance and
pointer production. Deriving those two independently is how a frontend
ends up accepting one family while producing the other: it would speak
v25 inbound and v24 outbound, and neither side could tell.
Acceptance refuses both wrong-family cases, atomically: a mapped
session rejects legacy `Present` rather than painting a band whose
cells it cannot safely invert (G8b), and a legacy session rejects
`PresentMapped` (G8d). The mapped arm also refuses generation zero and
any generation BELOW the one held --- nondecreasing, so a frame delayed
across a hide cannot roll authority backward --- while a duplicate
frame at a HIGHER generation is still accepted, because the daemon has
re-keyed the mapping and echoing the stale value would have every
gesture refused.
Production goes through one family-aware sender used by both send
sites, so they cannot drift. A mapped session with no retained
generation sends NOTHING rather than the legacy variant: falling back
is the frontend half of the bypass, and the daemon refuses it anyway.
**And the live probe observed only the legacy family.** Left alone,
mapped production could have worked end to end while the probe reported
no panel --- a false negative in the one place that exists to tell us
the band is real. It matches both now.
One thing NOT done here, deliberately: the gesture-latch reset on an
identity change is R-d, owned by `panel-pointer-replay`. I had copied
it into the mapped arm before noticing `gesture_last_content_cell` does
not exist on this branch --- it is replay-lane state. Two branches
resetting the same latch would conflict at the rebase and neither would
own the contract, so this arm installs the frame and its generation and
nothing more.
Verified by exit status: clippy 0, `-p pmacs-gpu` 0 (271 passed).
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016bqGA6s9tTUFzYpbeW3tai
Levi Neuwirth
7e28eb8936