P1 — `PanelPointer` was missing the approved `buffer_id`. Q#BP16 gives it
and `panel_epoch` different jobs and neither subsumes the other:
`buffer_id` catches an A->B buffer replacement, `panel_epoch` catches
close/hide/reopen of the SAME persistent buffer, which a buffer id alone
cannot see. Added in the framing's field order, with a pin asserting each
field independently reaches the wire.
P1 — added parent criterion 39's transport-safety ratchet. It builds the
maximum legal panel payload, asserts the fixture actually spends the whole
aggregate glyph budget (otherwise the ratchet measures something smaller
than the worst case), asserts one byte more is rejected, and pins the
encoded `InstanceMessage::PanelFrame` below `MAX_FRAME_BYTES`. Shaped
`1 x MAX_PANEL_VISIBLE_CELLS` deliberately: no per-axis cap makes that a
legal panel geometry a terminal cannot express, so it is the worst case
the terminal's own ratchet never measured. Bitten by tripling the glyph
budget — 30,342,696 bytes against the 16 MiB cap.
P2 — the shared bounds were duplicated literals. `MAX_TERMINAL_GRAPHEME_BYTES`
now aliases `MAX_WIRE_GRID_GRAPHEME_BYTES`, so the terminal screen's
truncation (`src/terminal/screen.rs:697`, `:777`) and the validator cannot
drift. Two more had the same defect and are aliased too:
`MAX_TERMINAL_VISIBLE_CELLS` and `MAX_TERMINAL_FRAME_GLYPH_BYTES`.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RuhVYUPHXMHG8r2z4tsDPR
Both pins failed on the bump, which is what they exist for. The ladder
test now accepts 6..=21 and rejects 22, and the version assertion carries
the Stage 2 entry: four variants appended after their enum's final v20
variant, gated in both directions.
Also renames `protocol_version_is_twenty_for_gpu_initial_targets`, whose
name pinned the old number.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RuhVYUPHXMHG8r2z4tsDPR
Adds the four wire shapes Q#BP9 names, bumps the protocol to v21, and
factors the cell-grid validator so a panel frame shares the terminal's
rules without inheriting its PTY caps.
- `InstanceMessage::PanelFrame(PanelFramePayload)`, appended after
`InitialTargetResult`; `Absent` is an explicit authoritative state, not
silence, because the receiver retains its last valid frame.
- `FrontendEvent::{FrontendCellGeometry, PanelResizeRows, PanelPointer}`,
appended after `TerminalPointer`. Geometry is valid without a side
window — gating it on panel presence would deadlock the first open,
since the daemon needs columns before it can paint a first frame.
- `pmacs-protocol/src/wire_grid.rs` holds the shared rules: checked area,
visible-cell bound, cell count, cursor bounds, glyph legality,
wide-continuation topology, the aggregate glyph budget, and the
attachment rejection. The 512 per-axis caps, metadata, selection spans,
and the at_bottom/scroll_offset coupling stay terminal-only.
- The attachment rejection is deliberately shared despite its
terminal-side wording: panels render no attachments either, so sharing
it fails closed for both.
Both byte pins were falsified by revert: moving `PanelFrame` ahead of
`InitialTargetResult` shifts it 27 -> 28 and fails; moving the three
events ahead of `TerminalPointer` shifts it 12 -> 15 and fails.
The factoring changed no terminal acceptance — all 17 terminal tests pass
unchanged. It did surface a pre-existing coverage gap: those tests pin
the row cap but never the column cap, so widening `max_cols` to u32::MAX
left them green. `a_panel_wider_than_512_columns_is_legal_while_a_terminal_is_not`
now covers that direction.
The daemon projection, the epoch state machine, and the GPU band are
later slices of this stage.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RuhVYUPHXMHG8r2z4tsDPR
Levi Neuwirth