ci: [refactor] Move github_import_vs_env to python script

diff --git a/.github/ci-windows-cross.py b/.github/ci-windows-cross.py
index 13ca3b49..90cd59c7 100755
--- a/.github/ci-windows-cross.py
+++ b/.github/ci-windows-cross.py
@@ -134,13 +134,13 @@ def run_unit_tests():
 
 def main():
     parser = argparse.ArgumentParser(description="Utility to run Windows CI steps.")
-    steps = [
-        "print_version",
-        "check_manifests",
-        "prepare_tests",
-        "run_unit_tests",
-        "run_functional_tests",
-    ]
+    steps = list(map(lambda f: f.__name__, [
+        print_version,
+        check_manifests,
+        prepare_tests,
+        run_unit_tests,
+        run_functional_tests,
+    ]))
     parser.add_argument("step", choices=steps, help="CI step to perform.")
     args = parser.parse_args()
 
@@ -149,16 +149,7 @@ def main():
         str(Path.cwd() / "previous_releases"),
     )
 
-    if args.step == "print_version":
-        print_version()
-    elif args.step == "check_manifests":
-        check_manifests()
-    elif args.step == "prepare_tests":
-        prepare_tests()
-    elif args.step == "run_unit_tests":
-        run_unit_tests()
-    elif args.step == "run_functional_tests":
-        run_functional_tests()
+    exec(f'{args.step}()')
 
 
 if __name__ == "__main__":
diff --git a/.github/ci-windows.py b/.github/ci-windows.py
index caa2d52c..16d7db7a 100755
--- a/.github/ci-windows.py
+++ b/.github/ci-windows.py
@@ -38,6 +38,29 @@ GENERATE_OPTIONS = {
 }
 
 
+def github_import_vs_env(_ci_type):
+    vswhere_path = Path(os.environ["ProgramFiles(x86)"]) / "Microsoft Visual Studio" / "Installer" / "vswhere.exe"
+    installation_path = run(
+        [str(vswhere_path), "-latest", "-property", "installationPath"],
+        capture_output=True,
+        text=True,
+    ).stdout.strip()
+    vsdevcmd = Path(installation_path) / "Common7" / "Tools" / "vsdevcmd.bat"
+    comspec = os.environ["COMSPEC"]
+    output = run(
+        f'"{comspec}" /s /c ""{vsdevcmd}" -arch=x64 -no_logo && set"',
+        capture_output=True,
+        text=True,
+    ).stdout
+    github_env = os.environ["GITHUB_ENV"]
+    with open(github_env, "a") as env_file:
+        for line in output.splitlines():
+            if "=" not in line:
+                continue
+            name, value = line.split("=", 1)
+            env_file.write(f"{name}={value}\n")
+
+
 def generate(ci_type):
     command = [
         "cmake",
@@ -50,7 +73,7 @@ def generate(ci_type):
     run(command)
 
 
-def build():
+def build(_ci_type):
     command = [
         "cmake",
         "--build",
@@ -180,26 +203,18 @@ def run_tests(ci_type):
 def main():
     parser = argparse.ArgumentParser(description="Utility to run Windows CI steps.")
     parser.add_argument("ci_type", choices=GENERATE_OPTIONS, help="CI type to run.")
-    steps = [
-        "generate",
-        "build",
-        "check_manifests",
-        "prepare_tests",
-        "run_tests",
-    ]
+    steps = list(map(lambda f: f.__name__, [
+        github_import_vs_env,
+        generate,
+        build,
+        check_manifests,
+        prepare_tests,
+        run_tests,
+    ]))
     parser.add_argument("step", choices=steps, help="CI step to perform.")
     args = parser.parse_args()
 
-    if args.step == "generate":
-        generate(args.ci_type)
-    elif args.step == "build":
-        build()
-    elif args.step == "check_manifests":
-        check_manifests(args.ci_type)
-    elif args.step == "prepare_tests":
-        prepare_tests(args.ci_type)
-    elif args.step == "run_tests":
-        run_tests(args.ci_type)
+    exec(f'{args.step}("{args.ci_type}")')
 
 
 if __name__ == "__main__":
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9bc798dc..2059adc4 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -227,16 +227,9 @@ jobs:
 
       - *CHECKOUT
 
-      - &SET_UP_VS
-        name: Set up VS Developer Prompt
-        shell: pwsh -Command "$PSVersionTable; $PSNativeCommandUseErrorActionPreference = $true; $ErrorActionPreference = 'Stop'; & '{0}'"
-        run: |
-          $vswherePath = "${env:ProgramFiles(x86)}\Microsoft Visual Studio\Installer\vswhere.exe"
-          $installationPath = & $vswherePath -latest -property installationPath
-          & "${env:COMSPEC}" /s /c "`"$installationPath\Common7\Tools\vsdevcmd.bat`" -arch=x64 -no_logo && set" | foreach-object {
-            $name, $value = $_ -split '=', 2
-            echo "$name=$value" >> $env:GITHUB_ENV
-          }
+      - &IMPORT_VS_ENV
+        name: Import Visual Studio env vars
+        run: py -3 .github/ci-windows.py "standard" github_import_vs_env
 
       - name: Get tool information
         shell: pwsh
@@ -418,7 +411,7 @@ jobs:
       - name: Run bitcoind.exe
         run: py -3 .github/ci-windows-cross.py print_version
 
-      - *SET_UP_VS
+      - *IMPORT_VS_ENV
 
       - name: Check executable manifests
         run: py -3 .github/ci-windows-cross.py check_manifests