Per docs/pmacs-gpu-mouse-framing.md (resolves the deferred Q#B5):
a pixel frontend cannot express the daemon's cell coordinates —
inline adornments shift visual columns invisibly to cell space and
the design contract forbids hit-test round trips — so the frontend
hit-tests locally and ships source-byte gestures.
- protocol v5: FrontendEvent::Pointer { buffer_id, byte, kind, mods }
with PointerKind { Down, Drag, Up, DoubleDown }. Double-click
detection is frontend-side (only it knows pixel proximity).
SUPPORTED_PROTOCOL_VERSIONS gains 5; the send gate runs in the
frontend (an older instance cannot decode the variant).
- daemon: dispatch_pointer replays the existing mouse gesture
semantics in byte space against the semantic session's window —
Down places + anchors, Drag grows, Up collapses an empty click,
DoubleDown selects the word. Routed by the authenticated source
(CrdtOp/Viewport trust rule); hit bytes clamp + snap to UTF-8
boundaries (a hit can race an in-flight edit).
- word_range_at fix (pre-existing CUA bug the new test surfaced):
double-clicking a word's FIRST character selected the previous
word too — backward_word from pos sees the non-word char behind
the hit and crosses over; walk from pos + ch_len instead.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
