change default font to Segoe UI

[Jamiras]

Switches the default font from 8pt MS Sans Serif to 9pt Segoe UI as per https://learn.microsoft.com/en-us/windows/win32/uxguide/vis-fonts#guidelines:

and

For Segoe UI, use a 9 point font size or larger. The Segoe UI font is optimized for these sizes, so avoid using smaller sizes.

This should address https://discord.com/channels/310192285306454017/533411674162593812/1520495156569309205 and https://discord.com/channels/310192285306454017/1490680141741953275/1490680141741953275

Also selects a fixed-width font for address fields and code note fields (see https://discord.com/channels/310192285306454017/962817919698501702/1491071043757015172 and https://discord.com/channels/310192285306454017/310195377993416714/1520816008653308015)

Before:

After:

Because we're using a 9pt font instead of an 8pt font, there's one less result shown, and one less line of memory at the same window size.