remove: drop Wayland frontend

docs/PROVENANCE.md

@@ -72,26 +72,6 @@ are `/usr/share/licenses/ttf-dejavu/LICENSE` and
 as the DejaVu custom license and CC0 1.0, respectively.  These packages are
 test fixtures, not names or paths hard-coded into the daemon.
 
-## Generated Wayland protocol code
-
-The four checked-in Wayland protocol C/header files were added in commit
-`7629ec5fe8976812655c9d12b447a62abc8bb671`:
-
-- `input-method-unstable-v2-client-protocol.h`
-- `input-method-unstable-v2-protocol.c`
-- `virtual-keyboard-unstable-v1-client-protocol.h`
-- `virtual-keyboard-unstable-v1-protocol.c`
-
-Their embedded notices identify the protocols as input-method-unstable-v2
-and virtual-keyboard-unstable-v1 and include the applicable MIT-style license
-terms.  The input-method files report generation by wayland-scanner 1.21.0;
-the virtual-keyboard files report wayland-scanner 1.23.1.  The source XML
-files and their upstream repository revisions were not committed or recorded
-in history, so these generated files cannot honestly be regenerated
-byte-for-byte from repository artifacts.  Do not edit them manually.  A
-future regeneration should commit the source XML or record its immutable
-upstream revision and the scanner command/version.
-
 ## Git submodules
 
 `cutest` is pinned by the repository as the unit-test framework.  XIM uses