lint: ruff clean services/ (autofix + manual + ignore E741)

- 24 autofix safe (SIM105 contextlib.suppress, F401 unused imports,
  I001 import order, B007 unused loop var, F811 redef, F841 unused).
- 15 unsafe-fix (UP038 X|Y in isinstance, SIM108 ternary, ecc.).
- Manual fix: SIM102 nested if in deribit term_structure, E402 imports
  in test_cot.py + sentiment server.py.
- Ignore E741 (variabili 'l' in list comprehensions deribit/client.py
  — stilistico, non bug).

Tests: 478/478 verdi.

services/mcp-macro/tests/test_cot.py

@@ -1,6 +1,11 @@
 from __future__ import annotations
 
-from mcp_macro.cot import classify_extreme, compute_percentile
+from mcp_macro.cot import (
+    classify_extreme,
+    compute_percentile,
+    parse_disagg_row,
+    parse_tff_row,
+)
 
 
 def test_compute_percentile_basic():
@@ -44,9 +49,6 @@ def test_classify_extreme_none_input():
     assert classify_extreme(None) == "neutral"
 
 
-from mcp_macro.cot import parse_disagg_row, parse_tff_row
-
-
 # Payload Socrata reale (subset campi rilevanti, valori arbitrari per test)
 TFF_SOCRATA_ROW = {
     "report_date_as_yyyy_mm_dd": "2026-04-22T00:00:00.000",