The nvngx.dll bundled from the OptiScaler v0.7.8-pre0 nightly was the
real NVIDIA DLSS 3.10.3 production runtime (47 MB).  Inspection of its
PE export table showed it is missing 18 NVSDK_NGX_* symbols introduced
in DLSS SDK 3.1+ that every modern DLSS-enabled title calls at init:

  NVSDK_NGX_D3D12_AllocateParameters / DestroyParameters
  NVSDK_NGX_D3D12_GetCapabilityParameters / GetParameters
  NVSDK_NGX_D3D12_Init_with_ProjectID / Init_ProjectID
  NVSDK_NGX_UpdateFeature
  (plus D3D11 and Vulkan equivalents)

OptiScaler 0.9.0-final's own NGX proxy layer exports all of these and
handles all NGX interception internally.  Shipping the bare NVIDIA DLL
alongside it caused export-not-found failures on Proton when any code
path bypassed OptiScaler's hooks and resolved directly against the file.
The OptiScaler 0.9.0-final release notes also explicitly advise Linux
users to delete nvngx.dll when upgrading.

Changes:
- package.json: remove nvngx.dll from remote_binary download list
- main.py SUPPORT_FILES: remove nvngx.dll (no longer staged to fgmod/)
- main.py extract_static_optiscaler: remove nvngx.dll from additional_files;
  add explanatory comment for future reference
- main.py check_fgmod_path: remove nvngx.dll from required-file check
- fgmod.sh: remove the cp line that deployed nvngx.dll into game dirs

nvngx.dll is intentionally kept in INJECTOR_FILENAMES (main.py) and in
the fgmod.sh pre-patch rm and fgmod-uninstaller.sh cleanup so that any
copy placed by a previous plugin version is swept from game directories
on the next patch or uninstall.

feat: AppID-based patch/unpatch with multi-library Steam discovery and marker tracking

Opti 090 final