Fix trip map unbooked flight pins and timezone-safe busy date comparisons

tests/test_busy_timezone.py

@@ -0,0 +1,35 @@
+"""Regression tests for timezone handling in busy location logic."""
+
+from datetime import date, datetime, timezone
+
+import agenda.busy
+from agenda.types import Trip
+
+
+def test_mixed_naive_and_aware_arrivals_do_not_crash() -> None:
+    """Most recent travel should compare mixed timezone styles safely."""
+    trips = [
+        Trip(
+            start=date(2099, 12, 30),
+            travel=[
+                {
+                    "type": "flight",
+                    "arrive": datetime(2100, 1, 1, 10, 0, 0),
+                    "to": "CDG",
+                    "to_airport": {"country": "fr", "city": "Paris"},
+                },
+                {
+                    "type": "flight",
+                    "arrive": datetime(2100, 1, 1, 12, 0, 0, tzinfo=timezone.utc),
+                    "to": "AMS",
+                    "to_airport": {"country": "nl", "city": "Amsterdam"},
+                },
+            ],
+        )
+    ]
+
+    location = agenda.busy._find_most_recent_travel_before_date(date(2100, 1, 1), trips)
+    assert location is not None
+    assert location[0] == "Amsterdam"
+    assert location[1] is not None
+    assert location[1].alpha_2 == "NL"