feat: add catlog command, agent flag reorder, and TUI polish

- Add `coinhunter catlog` with limit/offset pagination for audit logs
- Optimize audit log reading with deque to avoid loading all history
- Allow `-a/--agent` flag after subcommands
- Fix upgrade spinner artifact and empty line issues
- Render audit log TUI as timeline with low-saturation event colors
- Convert audit timestamps to local timezone in TUI
- Remove futures-related capabilities
- Add conda environment.yml for development
- Bump version to 2.0.9 and update README

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

tests/test_trade_service.py

@@ -20,7 +20,9 @@ class FakeSpotClient:
 class TradeServiceTestCase(unittest.TestCase):
     def test_spot_market_buy_dry_run_does_not_call_client(self):
         events = []
-        with patch.object(trade_service, "audit_event", side_effect=lambda event, payload: events.append((event, payload))):
+        with patch.object(
+            trade_service, "audit_event", side_effect=lambda event, payload: events.append((event, payload))
+        ):
             client = FakeSpotClient()
             payload = trade_service.execute_spot_trade(
                 {"trading": {"dry_run_default": False}},