feat: Default Plotly map colors

[bmingles]

• Added theme variables for Plotly map colors. Wired them up to the default layout
• Removed unused chart theme variables
• Fixed scroll issue in styleguide

Testing
Here's a Python snippet that can be used to see the map colors

import deephaven.plot.express as dx
from deephaven import time_table
import random 

def update(fig):
    pass

sourceh = time_table("PT1S").update(formulas=[
    "X = (float) random.uniform(-90, 90)", 
    "Y = (float) random.uniform(-180, 180)", 
    "Z = (float)random.gauss(3, 3)",
    "l1 = i % 20",
    "l2 = i % 30",
    ])

figs = dx.scatter_geo(
    sourceh, 
    lat="X", 
    lon="Y", 
    by="l1", 
    size="Z",
    color_discrete_sequence=["salmon", "lemonchiffon"],
    projection="natural earth",
    unsafe_update_figure=update
)

[codecov]

Codecov Report

Attention: 3 lines in your changes are missing coverage. Please review.

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Files	Patch %	Lines
...ackages/code-studio/src/styleguide/SamplesMenu.tsx	25.00%	3 Missing ⚠️

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[mattrunyon]

@dsmmcken Should we remove the frame? We can control framecolor, framewidth, and showframe

[mattrunyon]

Need to add geo.bgcolor. I'd say just set it to plot_bgcolor instead of making a separate variable for it

[mattrunyon]

I changed the bgcolor to plot_bgcolor and set framecolor to red just to illustrate. This is what happens when you zoom out. The current changes don't set geo.bgcolor

The frame is drawn around the map or the entire visible area if it extends past the visible map. So maybe we want a slightly different bgcolor to match the panel background and no frame

[dsmmcken]

In your example, I would expect the area inside the red line to have the slightly lighter bg color, and everything outside to have the content-bg color.

Then hiding the frame is fine.

[bmingles]

I set bgcolor to paper_bgcolor instead of plot_bgcolor so that it gets the outer color and keeps the frame boundary as the delineation of the 2 colors