feat: add detailed logging to all API routes and global access log middleware

Each API module now logs:
- evaluations: trigger (scenario path, task_id), status polls, list
- runs: list (count), detail (run_id, metrics, sample counts)
- scenarios: list (total, valid, error counts)
- pipeline: submit (docs_path, models, max_docs), status polls, list
- llm_profiles: CRUD ops (name, model, id), probe/test (model, ok, latency), apply (patched fields)
- score: already had per-request logging

Global middleware (webapp.access logger):
- Every API request: METHOD path -> status (latency_ms) at INFO
- Static file requests demoted to DEBUG to reduce noise

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

webapp/api/scenarios.py

@@ -2,15 +2,20 @@
 
 from __future__ import annotations
 
+import logging
+
 from fastapi import APIRouter
 
 from webapp.services import scenario_scanner
 
 router = APIRouter(prefix="/api/scenarios", tags=["scenarios"])
+logger = logging.getLogger("webapp.api.scenarios")
 
 
 @router.get("")
 def get_scenarios() -> dict[str, list]:
     """Return every scenario file found under the scenarios/ directory."""
     scenarios = scenario_scanner.list_scenarios()
+    valid = sum(1 for s in scenarios if not s.error)
+    logger.info("[get_scenarios] total=%d  valid=%d  errors=%d", len(scenarios), valid, len(scenarios) - valid)
     return {"scenarios": [item.model_dump() for item in scenarios]}