Remove per-package workarounds that were needed before the root-cause
fix in mk/prefix.mk (which adds #include <stdlib.h> to GCC's <cstdlib>
header at prefix build time). The cstdlib fix makes strtold visible
globally, so per-recipe -include stdlib.h and P1-*.patch are redundant.
Reverted:
- redox-toolchain.cmake: removed -include stdlib.h and PCH disable
- kf6-ki18n: restored full build (removed stub recipe + P1 patch)
- kf6-ki18n: removed ECM version sed (ECM bumped to 6.11.0 already)
- redbear-greeter: removed #include <stdlib.h> workarounds in source
- local/patches/kf6-ki18n/: removed unused P1 patch directory
Consolidate the active desktop path around redbear-full while landing the greeter/session stack and the runtime fixes needed to keep Wayland and KWin bring-up moving forward.