Close local release-quality gaps and reconcile workplan status

Assistant: codex
Assistant-Model: gpt-6-astra
Assistant-Session: 01a0e332-3365-77c0-8491-084e9ea33ac1

tests/test_async.py

@@ -3,11 +3,12 @@ Tests for async_execute_prompt (FR-3).
 """
 
 import asyncio
+
 import pytest
 
-from llm_connect.models import RunConfig, BudgetTracker
 from llm_connect.adapter import MockLLMAdapter
 from llm_connect.exceptions import LLMBudgetExceededError
+from llm_connect.models import BudgetTracker, RunConfig
 
 
 class TestAsyncExecutePrompt:
@@ -46,7 +47,6 @@ class TestAsyncExecutePrompt:
 
     def test_concurrent_faster_than_sequential(self):
         """Gathering N async calls should not be N× slower than one call."""
-        import time
 
         adapter = MockLLMAdapter()
         config = RunConfig()