Windows: Build error when using a local copy of ZNN SDK

[sol-znn]

I saw a vague error in the Flutter build logs when sourcing the ZNN SDK from disk.
The build process works well if the package is sourced from Github, but fails otherwise.

Creating this ticket to track the issue. Should confirm behavior on Linux, as well.

Repro
Update pubspec.yaml reference for znn_sdk_dart

  znn_sdk_dart:
    path:
      ../znn_sdk_dart

Current solution: syrius/windows/CMakeLists.txt

# Leveraging flutter to identify dependency locations
file(STRINGS "${SYRIUS_PROJECT_DIRECTORY}/.dart_tool/package_config.json"
  ZNN_SDK_DART_PATH REGEX "(rootUri).*(znn_sdk_dart).*(\/|)\"," )

string(REPLACE "\"rootUri\": \"" "" ZNN_SDK_DART_PATH "${ZNN_SDK_DART_PATH}")
string(REPLACE "file:\/\/\/" "" ZNN_SDK_DART_PATH "${ZNN_SDK_DART_PATH}")
string(REPLACE "/\"," "" ZNN_SDK_DART_PATH "${ZNN_SDK_DART_PATH}")
string(REPLACE "\"," "" ZNN_SDK_DART_PATH "${ZNN_SDK_DART_PATH}")
string(STRIP "${ZNN_SDK_DART_PATH}" ZNN_SDK_DART_PATH)

I tried to combine some of these REPLACE lines with more complex regex but cmake wasn't producing the expected result.