Fix numpad rod mapping on terminals without keypad constants

src/reactor_sim/dashboard.py

@@ -17,17 +17,29 @@ from .state import PlantState
 
 LOGGER = logging.getLogger(__name__)
 
-_NUMPAD_ROD_KEYS = {
-    curses.KEY_C1: 0.1,  # numpad 1
-    curses.KEY_C2: 0.2,  # numpad 2
-    curses.KEY_C3: 0.3,  # numpad 3
-    curses.KEY_B1: 0.4,  # numpad 4
-    curses.KEY_B2: 0.5,  # numpad 5
-    curses.KEY_B3: 0.6,  # numpad 6
-    curses.KEY_A1: 0.7,  # numpad 7
-    curses.KEY_A2: 0.8,  # numpad 8
-    curses.KEY_A3: 0.9,  # numpad 9
+
+def _build_numpad_mapping() -> dict[int, float]:
+    # Use keypad matrix constants when available; skip missing ones to avoid import errors on some terminals.
+    mapping: dict[int, float] = {}
+    table = {
+        "KEY_C1": 0.1,  # numpad 1
+        "KEY_C2": 0.2,  # numpad 2
+        "KEY_C3": 0.3,  # numpad 3
+        "KEY_B1": 0.4,  # numpad 4
+        "KEY_B2": 0.5,  # numpad 5
+        "KEY_B3": 0.6,  # numpad 6
+        "KEY_A1": 0.7,  # numpad 7
+        "KEY_A2": 0.8,  # numpad 8
+        "KEY_A3": 0.9,  # numpad 9
     }
+    for name, value in table.items():
+        code = getattr(curses, name, None)
+        if code is not None:
+            mapping[code] = value
+    return mapping
+
+
+_NUMPAD_ROD_KEYS = _build_numpad_mapping()
 
 
 @dataclass