The VK key-event vocabulary cannot express text an input method COMMITS
(autocorrect, gesture typing, non-Latin scripts, emoji). Add a first-class
text event and negotiate it:
- punktfunk-core: InputKind::TextInput (= 15) carries one Unicode scalar per
event in `code`; HOST_CAP_TEXT_INPUT (0x04) in Welcome::host_caps.
- Host advertises the cap only where the session's inject backend can type
text: Windows SendInput (KEYEVENTF_UNICODE, surrogate-pair aware) and the
Linux wlroots backend — a dedicated second zwp_virtual_keyboard whose xkb
keymap grows Unicode keysyms on demand (the wtype model), so keymap
re-uploads never disturb the main device's layout/modifier state. The
KWin-fake-input/libei/gamescope backends can only press layout keycodes, so
those sessions don't set the bit and clients keep the VK fallback.
- GameStream plane: Moonlight's UTF-8 text packet (MAGIC_UTF8, previously
recognized-and-dropped) now decodes to the same TextInput events.
- Android: KeyCaptureView picks a real editable InputConnection when the host
has the cap — the IME runs its full machinery, mirrored to the host live via
common-prefix diffs of the composition (backspaces + new suffix), with
setComposingRegion adopting committed text so autocorrect-revert flows diff
instead of retyping; newline→Enter, deleteSurroundingText→Backspace/Delete.
Older hosts keep the TYPE_NULL raw-key path unchanged.
- keymap: media VKs (0xB0-0xB3) → evdev so the Android media keys land on
Linux hosts too.
Verified: punktfunk-core + host gamestream + pf-inject tests green on Linux
(Ubuntu box), clippy clean; Android app+native builds.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>