Consolidated from the qa-input-collision-fix-0.1.0 work, applied onto main so
only the changes main genuinely lacks are carried (main already merged the
walkable-demo/collision work independently).
- fix(input): populate the UE 5.8 FInputMappingContextMappingData
DefaultKeyMappings field in ue_create_input_assets.py (the runtime reads
GetMappings()->DefaultKeyMappings.Mappings; the script previously wrote only
the deprecated 'mappings' array, so the cooked game had 0 runtime mappings
and every key silently did nothing — in packaged AND PIE). Regenerated
IMC_Default.uasset. WASD/mouse/Space/R/Escape verified working.
- fix(build): drop editor-only APIs that break the game target build —
UStaticMesh::PostEditChange() (GigLineAssetTools) and AActor::GetActorLabel()
(character ground probe). GigLine and GigLineEditor now both compile clean.
- tools: OS-level uinput input harness (input_emulation.py + input_test.py) and
run_pie.sh for PIE isolation; document the PIE-vs-packaged input test in
Docs/build.md. Removed the temporary SIM/EI/screenshot diagnostics from the
character.
