chore: enable pyupgrade fixes (#1806)

# What does this PR do?

The goal of this PR is code base modernization.

Schema reflection code needed a minor adjustment to handle UnionTypes
and collections.abc.AsyncIterator. (Both are preferred for latest Python
releases.)

Note to reviewers: almost all changes here are automatically generated
by pyupgrade. Some additional unused imports were cleaned up. The only
change worth of note can be found under `docs/openapi_generator` and
`llama_stack/strong_typing/schema.py` where reflection code was updated
to deal with "newer" types.

Signed-off-by: Ihar Hrachyshka <ihar.hrachyshka@gmail.com>

llama_stack/distribution/utils/config.py

@@ -4,10 +4,10 @@
 # This source code is licensed under the terms described in the LICENSE file in
 # the root directory of this source tree.
 
-from typing import Any, Dict
+from typing import Any
 
 
-def redact_sensitive_fields(data: Dict[str, Any]) -> Dict[str, Any]:
+def redact_sensitive_fields(data: dict[str, Any]) -> dict[str, Any]:
     """Redact sensitive information from config before printing."""
     sensitive_patterns = ["api_key", "api_token", "password", "secret"]
 
@@ -18,7 +18,7 @@ def redact_sensitive_fields(data: Dict[str, Any]) -> Dict[str, Any]:
             return [_redact_value(i) for i in v]
         return v
 
-    def _redact_dict(d: Dict[str, Any]) -> Dict[str, Any]:
+    def _redact_dict(d: dict[str, Any]) -> dict[str, Any]:
         result = {}
         for k, v in d.items():
             if any(pattern in k.lower() for pattern in sensitive_patterns):

llama_stack/distribution/utils/context.py

@@ -4,14 +4,15 @@
 # This source code is licensed under the terms described in the LICENSE file in
 # the root directory of this source tree.
 
+from collections.abc import AsyncGenerator
 from contextvars import ContextVar
-from typing import AsyncGenerator, List, TypeVar
+from typing import TypeVar
 
 T = TypeVar("T")
 
 
 def preserve_contexts_async_generator(
-    gen: AsyncGenerator[T, None], context_vars: List[ContextVar]
+    gen: AsyncGenerator[T, None], context_vars: list[ContextVar]
 ) -> AsyncGenerator[T, None]:
     """
     Wraps an async generator to preserve context variables across iterations.

llama_stack/distribution/utils/prompt_for_config.py

@@ -8,12 +8,11 @@ import inspect
 import json
 import logging
 from enum import Enum
-from typing import Any, List, Literal, Optional, Type, Union, get_args, get_origin
+from typing import Annotated, Any, Literal, Union, get_args, get_origin
 
 from pydantic import BaseModel
 from pydantic.fields import FieldInfo
 from pydantic_core import PydanticUndefinedType
-from typing_extensions import Annotated
 
 log = logging.getLogger(__name__)
 
@@ -21,7 +20,7 @@ log = logging.getLogger(__name__)
 def is_list_of_primitives(field_type):
     """Check if a field type is a List of primitive types."""
     origin = get_origin(field_type)
-    if origin is List or origin is list:
+    if origin is list or origin is list:
         args = get_args(field_type)
         if len(args) == 1 and args[0] in (int, float, str, bool):
             return True
@@ -53,7 +52,7 @@ def get_non_none_type(field_type):
     return next(arg for arg in get_args(field_type) if arg is not type(None))
 
 
-def manually_validate_field(model: Type[BaseModel], field_name: str, value: Any):
+def manually_validate_field(model: type[BaseModel], field_name: str, value: Any):
     validators = model.__pydantic_decorators__.field_validators
     for _name, validator in validators.items():
         if field_name in validator.info.fields:
@@ -126,7 +125,7 @@ def prompt_for_discriminated_union(
 #
 # doesn't support List[nested_class] yet or Dicts of any kind. needs a bunch of
 # unit tests for coverage.
-def prompt_for_config(config_type: type[BaseModel], existing_config: Optional[BaseModel] = None) -> BaseModel:
+def prompt_for_config(config_type: type[BaseModel], existing_config: BaseModel | None = None) -> BaseModel:
     """
     Recursively prompt the user for configuration values based on a Pydantic BaseModel.