style: apply ruff's automatic fixes and formatter

Mechanical only, and separated from the judgment calls that follow so the
reviewable changes are not buried in a 98-file whitespace diff.

227 automatic fixes: 60 blank lines carrying whitespace, 60 unsorted import
blocks, 34 Optional[X] to X | None, 28 unused imports, 16 deprecated typing
imports, 12 datetime.timezone.utc to datetime.UTC, and assorted smaller
modernisations. Then `ruff format` over src and tests: 98 files reformatted,
35 already conforming.

No file among the unused-import findings defines __all__ or is an __init__.py,
so nothing here removes a re-export.

`make test`: 658 passed, unchanged from HEAD.

Two things observed while verifying, neither addressed here:

`pytest tests/` cannot collect — tests/e2e/test_orchestration_e2e.py uses an
`e2e` marker that is not registered, and the config is strict about markers.
This fails identically at HEAD, so it predates this change; `make test` passes
because it ignores tests/e2e, tests/integration and tests/contracts.

test_tatlock_tool_call_logging_calculator is flaky. It failed once in a full run
with these changes and passed on the next, passes in isolation with them, and
fails in isolation at HEAD. It is order- or timing-dependent, not a regression
from this commit — established by running the full suite both ways rather than
by reasoning about which change could have caused it.

Co-Authored-By: Claude <noreply@anthropic.com>

src/agents/lorem_tester.py

@@ -12,16 +12,16 @@ infrastructure is real production code.
 import asyncio
 import random
 import secrets
-from typing import AsyncGenerator, Any
+from collections.abc import AsyncGenerator
+from typing import Any
 
 from src.agents.base import AgentInterface, OutputItem
 from src.core.exceptions import (
-    RateLimitError,
-    ContextLengthError,
     APIError,
+    ContextLengthError,
+    RateLimitError,
 )
 
-
 # Mock lorem ipsum content
 LOREM_PARAGRAPHS = [
     "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.",
@@ -46,33 +46,27 @@ MOCK_TOOLS = [
         "description": "Search the knowledge base for relevant information",
         "parameters": {
             "type": "object",
-            "properties": {
-                "query": {"type": "string", "description": "Search query"}
-            },
-            "required": ["query"]
-        }
+            "properties": {"query": {"type": "string", "description": "Search query"}},
+            "required": ["query"],
+        },
     },
     {
         "name": "calculate",
         "description": "Perform mathematical calculations",
         "parameters": {
             "type": "object",
-            "properties": {
-                "expression": {"type": "string", "description": "Math expression"}
-            },
-            "required": ["expression"]
-        }
+            "properties": {"expression": {"type": "string", "description": "Math expression"}},
+            "required": ["expression"],
+        },
     },
     {
         "name": "get_weather",
         "description": "Get current weather for a location",
         "parameters": {
             "type": "object",
-            "properties": {
-                "location": {"type": "string", "description": "City name"}
-            },
-            "required": ["location"]
-        }
+            "properties": {"location": {"type": "string", "description": "City name"}},
+            "required": ["location"],
+        },
     },
 ]
 
@@ -109,7 +103,7 @@ class LoremTesterAgent(AgentInterface):
         temperature: float = 1.0,
         max_tokens: int | None = None,
         stop: list[str] | None = None,
-        **kwargs: Any
+        **kwargs: Any,
     ) -> AsyncGenerator[OutputItem, None]:
         """
         Generate mock response with reasoning, tools, and content.
@@ -123,8 +117,7 @@ class LoremTesterAgent(AgentInterface):
         # 1. Yield reasoning item if requested
         if reasoning and reasoning.get("summary") == "auto":
             yield await self._create_reasoning_item(
-                messages,
-                effort=reasoning.get("effort", "medium")
+                messages, effort=reasoning.get("effort", "medium")
             )
 
         # 2. Randomly yield function calls if tools available (30% chance)
@@ -150,7 +143,7 @@ class LoremTesterAgent(AgentInterface):
             "reasoning": True,
             "tools": True,
             "vision": False,  # Not yet
-            "audio": False,   # Not yet
+            "audio": False,  # Not yet
         }
 
     # Private helper methods
@@ -179,9 +172,7 @@ class LoremTesterAgent(AgentInterface):
             raise APIError("Invalid tool call: tool 'nonexistent' not found (mock trigger)")
 
     async def _create_reasoning_item(
-        self,
-        messages: list[dict],
-        effort: str = "medium"
+        self, messages: list[dict], effort: str = "medium"
     ) -> OutputItem:
         """Create a reasoning output item with mock thinking steps."""
 
@@ -200,23 +191,17 @@ class LoremTesterAgent(AgentInterface):
         steps = random.sample(REASONING_STEPS, min(num_steps, len(REASONING_STEPS)))
 
         return OutputItem(
-            type="reasoning",
-            id=f"rs_{generate_id()}",
-            summary=steps,
-            status="completed"
+            type="reasoning", id=f"rs_{generate_id()}", summary=steps, status="completed"
         )
 
-    async def _create_tool_calls(
-        self,
-        tools: list[dict]
-    ) -> AsyncGenerator[OutputItem, None]:
+    async def _create_tool_calls(self, tools: list[dict]) -> AsyncGenerator[OutputItem, None]:
         """Create mock function call output items."""
 
         # Randomly select 1-2 tools to "call"
         num_calls = random.randint(1, 2)
         selected_tools = random.sample(
-            MOCK_TOOLS[:min(len(MOCK_TOOLS), len(tools))],
-            min(num_calls, len(MOCK_TOOLS), len(tools))
+            MOCK_TOOLS[: min(len(MOCK_TOOLS), len(tools))],
+            min(num_calls, len(MOCK_TOOLS), len(tools)),
         )
 
         for tool in selected_tools:
@@ -228,7 +213,7 @@ class LoremTesterAgent(AgentInterface):
                 id=f"fc_{generate_id()}",
                 name=tool["name"],
                 arguments=args,
-                status="completed"
+                status="completed",
             )
 
     def _generate_mock_args(self, tool: dict) -> str:
@@ -254,11 +239,7 @@ class LoremTesterAgent(AgentInterface):
             # Generic mock arguments
             return json.dumps({"input": "mock_value"})
 
-    async def _create_message_item(
-        self,
-        messages: list[dict],
-        temperature: float
-    ) -> OutputItem:
+    async def _create_message_item(self, messages: list[dict], temperature: float) -> OutputItem:
         """Create final message output item with lorem ipsum content."""
 
         # Select random lorem ipsum paragraphs
@@ -270,10 +251,6 @@ class LoremTesterAgent(AgentInterface):
             type="message",
             id=f"msg_{generate_id()}",
             role="assistant",
-            content=[{
-                "type": "output_text",
-                "text": content,
-                "annotations": []
-            }],
-            status="completed"
+            content=[{"type": "output_text", "text": content, "annotations": []}],
+            status="completed",
         )