feat: add --run to llama stack build (#1156)

# What does this PR do?

--run runs the stack that was just build using the same arguments during
the build process (image-name, type, etc)

This simplifies the workflow a lot and makes the UX better for most
local users trying to get started rather than having to match the flags
of the two commands (build and then run)

Also, moved `ImageType` to distribution.utils since there were circular
import errors with its old location

## Test Plan

tested locally using the following command: 

`llama stack build --run --template ollama --image-type venv`

Signed-off-by: Charlie Doern <cdoern@redhat.com>

llama_stack/distribution/build.py

@@ -7,7 +7,6 @@
 import importlib.resources
 import logging
 import sys
-from enum import Enum
 from pathlib import Path
 from typing import Dict, List
 
@@ -18,6 +17,7 @@ from llama_stack.distribution.datatypes import BuildConfig, Provider
 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.image_types import ImageType
 from llama_stack.providers.datatypes import Api
 
 log = logging.getLogger(__name__)
@@ -33,12 +33,6 @@ SERVER_DEPENDENCIES = [
 ]
 
 
-class ImageType(Enum):
-    container = "container"
-    conda = "conda"
-    venv = "venv"
-
-
 class ApiInput(BaseModel):
     api: Api
     provider: str