Add FSR3 Generic API path and harden runtime diagnostics

- AmdFsr3Runtime now probes both the legacy ffxFsr3* API and the newer
  generic ffxCreateContext/ffxDispatch API; selects whichever the loaded
  runtime library exports (GenericApi takes priority fallback)
- Generic API path implements full upscale + frame-generation context
  creation, configure, dispatch, and destroy lifecycle
- dlopen error captured and surfaced in lastError_ on Linux so runtime
  initialization failures are actionable
- FSR3 runtime init failure log now includes path kind, error string,
  and loaded library path for easier debugging
- tools/generate_ffx_sdk_vk_permutations.sh added: auto-bootstraps
  missing VK permutation headers; DXC auto-downloaded on Linux/Windows
  MSYS2; macOS reads from PATH (CI installs via brew dxc)
- CMakeLists: add upscalers/include to probe include dirs, invoke
  permutation script before SDK build, scope FFX pragma/ODR warning
  suppressions to affected TUs, add runtime-copy dependency on wowee
- UI labels updated from "FSR2" → "FSR3" in settings, tuning panel,
  performance HUD, and combo boxes
- CI macOS job now installs dxc via Homebrew for permutation codegen

README.md

@@ -278,6 +278,7 @@ make -j$(nproc)
 - All build jobs are AMD-FSR2-only (`WOWEE_ENABLE_AMD_FSR2=ON`) and explicitly build `wowee_fsr2_amd_vk`
 - Each job clones AMD's FSR2 SDK and FidelityFX-SDK (`Kelsidavis/FidelityFX-SDK`, `main` by default)
 - Linux CI validates FidelityFX-SDK Kits framegen headers
+- FSR3 Path A runtime build auto-bootstraps missing VK permutation headers via `tools/generate_ffx_sdk_vk_permutations.sh`
 - CI builds `wowee_fsr3_framegen_amd_vk_probe` when that target is generated for the detected SDK layout
 - If FSR2 generated Vulkan permutation headers are absent upstream, WoWee bootstraps them from `third_party/fsr2_vk_permutations`
 - Container build via `container/build-in-container.sh` (Podman)