Column header names do not truncate properly with wide characters

[mattrunyon]

Description

Column header names are truncated based on an estimated width in GridRenderer.drawColumnHeader. This is problematic since column headers do not use a monospaced font. If there are many wide characters in a name, it can overflow the bounds instead of truncating.

Steps to reproduce

from deephaven import empty_table
t = empty_table(10).update(["X=ii", "MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM=ii"])

Expected results

The long column name with "M" (wide character) is truncated

Actual results

Versions

Engine Version: 0.37.0-SNAPSHOT
Web UI Version: 0.97.0
Java Version: 17.0.12
Barrage Version: 0.6.0
Browser Name: Chrome 130
OS Name: Linux
@deephaven/js-plugin-ui: 0.22.0
@deephaven/js-plugin-plotly-express: 0.11.2
@deephaven/js-plugin-matplotlib: 0.5.0