Add windows support for build execution (#889)

# What does this PR do?

This PR implements windows platform support for build_container.sh
execution from terminal. Additionally, it resolves "no support for
Terminos and PTY for Window PC" issues.

- [x] Addresses issue (#issue)
Releates issues: https://github.com/meta-llama/llama-stack/issues/826,
https://github.com/meta-llama/llama-stack/issues/726

## Test Plan

Changes were tested manually by executing standard scripts from LLama
guide:
- llama stack build --template ollama --image-type container
- llama stack build --list-templates
- llama stack build

## Sources

Please link relevant resources if necessary.


## Before submitting

- [ ] This PR fixes a typo or improves the docs (you can dismiss the
other checks if that's the case).
- [x] Ran pre-commit to handle lint / formatting issues.
- [x] Read the [contributor
guideline](https://github.com/meta-llama/llama-stack/blob/main/CONTRIBUTING.md),
      Pull Request section?
- [ ] Updated relevant documentation.
- [ ] Wrote necessary unit or integration tests.

llama_stack/distribution/build.py

@@ -21,7 +21,7 @@ from llama_stack.distribution.distribution import get_provider_registry
 
 from llama_stack.distribution.utils.config_dirs import BUILDS_BASE_DIR
 
-from llama_stack.distribution.utils.exec import run_command, run_with_pty
+from llama_stack.distribution.utils.exec import run_command, run_with_pty, run_with_win
 from llama_stack.providers.datatypes import Api
 
 log = logging.getLogger(__name__)
@@ -157,7 +157,9 @@ def build_image(
 
     is_terminal = sys.stdin.isatty()
     if is_terminal:
-        return_code = run_with_pty(args)
+        return_code = (
+            run_with_win(args) if sys.platform.startswith("win") else run_with_pty(args)
+        )
     else:
         return_code = run_command(args)
 

llama_stack/distribution/utils/exec.py

@@ -7,12 +7,10 @@
 import errno
 import logging
 import os
-import pty
 import select
 import signal
 import subprocess
 import sys
-import termios
 
 log = logging.getLogger(__name__)
 
@@ -20,6 +18,9 @@ log = logging.getLogger(__name__)
 # run a command in a pseudo-terminal, with interrupt handling,
 # useful when you want to run interactive things
 def run_with_pty(command):
+    import pty
+    import termios
+
     master, slave = pty.openpty()
 
     old_settings = termios.tcgetattr(sys.stdin)
@@ -97,6 +98,40 @@ def run_with_pty(command):
     return process.returncode
 
 
+# run a command in a pseudo-terminal in windows, with interrupt handling,
+def run_with_win(command):
+    """
+    Alternative to run_with_pty for Windows platforms.
+    Runs a command with interactive support using subprocess directly.
+    """
+    try:
+        # For shell scripts on Windows, use appropriate shell
+        if isinstance(command, (list, tuple)):
+            if command[0].endswith(".sh"):
+                if os.path.exists("/usr/bin/bash"):  # WSL
+                    command = ["bash"] + command
+                else:
+                    # Use cmd.exe with bash while preserving all arguments
+                    command = ["cmd.exe", "/c", "bash"] + command
+
+        process = subprocess.Popen(
+            command,
+            shell=True,
+            universal_newlines=True,
+        )
+
+        process.wait()
+
+    except Exception as e:
+        print(f"Error: {str(e)}")
+        return 1
+    finally:
+        if process and process.poll() is None:
+            process.terminate()
+            process.wait()
+    return process.returncode
+
+
 def run_command(command):
     try:
         result = subprocess.run(command, capture_output=True, text=True, check=True)