Update port and improve axis label formatting

Changed FlaskUI port from 45678 to 8521 in app.py. Updated axis label formatting in viz.py to use nested 'text' property for Plotly compatibility and increased left margin in scatter2d layout.

Author: zpeng

app.py

@@ -561,5 +561,5 @@ def open_modal(unused_select_modal: Optional[int]) -> Dict[str, bool]:
         freeze_support()
 
         FlaskUI(
-            app=app.server, server="flask", port=45678, profile_dir_prefix="sensorview"
+            app=app.server, server="flask", port=8521, profile_dir_prefix="sensorview"
         ).run()

viz/viz.py

@@ -158,8 +158,8 @@ def get_heatmap(
             }
         ],
         "layout": {
-            "xaxis": {"title": x_label},
-            "yaxis": {"title": y_label},
+            "xaxis": {"title": {"text": x_label}},
+            "yaxis": {"title": {"text": y_label}},
         },
     }
 
@@ -200,7 +200,7 @@ def get_scatter2d(
     linewidth = kwargs.get("linewidth", 0)
 
     if margin is None:
-        margin = {"l": 40, "r": 40, "b": 40, "t": 60}
+        margin = {"l": 80, "r": 40, "b": 40, "t": 60}
 
     if x_label is None:
         x_label = x_key
@@ -236,8 +236,8 @@ def get_scatter2d(
                 }
             ],
             "layout": {
-                "xaxis": {"title": x_label},
-                "yaxis": {"title": y_label},
+                "xaxis": {"title": {"text": x_label}},
+                "yaxis": {"title": {"text": y_label}},
                 "margin": margin,
                 "uirevision": uirevision,
             },
@@ -269,8 +269,8 @@ def get_scatter2d(
         return {
             "data": data,
             "layout": {
-                "xaxis": {"title": x_label},
-                "yaxis": {"title": y_label},
+                "xaxis": {"title": {"text": x_label}},
+                "yaxis": {"title": {"text": y_label}},
                 "margin": margin,
                 "uirevision": uirevision,
             },