feat(pipeline): tests, docs, and ruff fixes (subtask 6/6)

- Add 29-test suite for all pipeline routes, data helpers, and query
  execution (test_pipeline.py); all 1333 tests pass
- Fix ruff UP041: asyncio.TimeoutError → TimeoutError in analytics.py
- Fix ruff UP036/F401: replace sys.version_info tomllib block with
  plain `import tomllib` (project requires Python 3.11+)
- Fix ruff F841: remove unused `cutoff` variable in pipeline_overview
- Update CHANGELOG.md with Pipeline Console entry
- Update PROJECT.md: add Pipeline Console to Admin Panel done list

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

web/src/padelnomics/admin/pipeline_routes.py

@@ -25,8 +25,7 @@ import logging
 import os
 import re
 import sqlite3
-import sys
-import time
+import tomllib
 from datetime import UTC, datetime, timedelta
 from pathlib import Path
 
@@ -307,18 +306,7 @@ def _load_workflows() -> list[dict]:
     if not _WORKFLOWS_TOML.exists():
         return []
 
-    if sys.version_info >= (3, 11):
-        import tomllib
-
-        data = tomllib.loads(_WORKFLOWS_TOML.read_text())
-    else:
-        # Fallback for older Python (shouldn't happen — project requires 3.11+)
-        try:
-            import tomli as tomllib  # type: ignore[no-redef]
-
-            data = tomllib.loads(_WORKFLOWS_TOML.read_text())
-        except ImportError:
-            return []
+    data = tomllib.loads(_WORKFLOWS_TOML.read_text())
 
     workflows = []
     for name, config in data.items():
@@ -422,9 +410,6 @@ async def pipeline_overview():
     latest_by_name = {r["extractor"]: r for r in latest_runs}
 
     # Enrich each workflow with its latest run data
-    cutoff = (datetime.now(UTC) - timedelta(hours=_STALE_THRESHOLD_HOURS)).strftime(
-        "%Y-%m-%dT%H:%M:%SZ"
-    )
     workflow_rows = []
     for wf in workflows:
         run = latest_by_name.get(wf["name"])

web/src/padelnomics/analytics.py

@@ -74,7 +74,7 @@ async def fetch_analytics(sql: str, params: list | None = None) -> list[dict[str
             asyncio.to_thread(_run),
             timeout=_QUERY_TIMEOUT_SECONDS,
         )
-    except asyncio.TimeoutError:
+    except TimeoutError:
         logger.error("DuckDB analytics query timed out after %ds: %.200s", _QUERY_TIMEOUT_SECONDS, sql)
         return []
     except Exception:
@@ -123,5 +123,5 @@ async def execute_user_query(
             asyncio.to_thread(_run),
             timeout=timeout_seconds,
         )
-    except asyncio.TimeoutError:
+    except TimeoutError:
         return [], [], f"Query timed out after {timeout_seconds}s.", 0.0