[DOCS] Example of .env about mumain

[Mosch0512]

I will add an wiki on how to get it going on Rider or CLion depending on what is better working here. Depending on if i get it running lol xD.

Edit:
For Windows only

[rafaelvieiras]

I extract all environment variables on project based on the pattern $(VAR) using this bash:

#!/bin/bash

PROJECT_DIR="./"

OUTPUT_FILE="unique_vars.txt"
TEMP_FILE="temp_vars.txt"

: >"$OUTPUT_FILE"
: >"$TEMP_FILE"

REGEX='\$\([a-zA-Z0-9_]*\)'

find "$PROJECT_DIR" -type f | while read -r file; do
    if [[ "$file" != "./$OUTPUT_FILE" && "$file" != "./$TEMP_FILE" ]]; then

        grep -oP "$REGEX" "$file" | while read -r var; do
            if ! grep -q "$var" "$TEMP_FILE"; then
                echo "$var" >>"$TEMP_FILE"
            fi
        done
    fi
done

sort "$TEMP_FILE" | uniq >"$OUTPUT_FILE"

rm "$TEMP_FILE"

cat "$OUTPUT_FILE"

The result is:

ci
CommonExecutablePath
Configuration
DXSDK_DIR
ExcludeRestorePackageImports
USERPROFILE
IntDir
LibraryPath
MSBuildThisFileDirectory
MU_SDK
NETFXKitsDir
NuGetPackageFolders
NuGetPackageRoot
NuGetProjectStyle
NuGetToolVersion
OutDir
PkgMicrosoft_CodeAnalysis_Analyzers
PkgMicrosoft_VisualStudio_Threading_Analyzers
PkgStyleCop_Analyzers_Unstable
Platform
ProjectAssetsFile
RestoreSuccess
RestoreTool
SolutionDir
TargetExt
TargetName
UserRootDir
VC_ExecutablePath_x86
VC_IncludePath
VC_LibraryPath_x86
VC_SourcePath
VCTargetsPath
WindowsSDK_IncludePath
WindowsSDK_LibraryPath_x86

I which this is correctly.