Web Viewer UI Improvements

[kwokcb]

Changes

• Add FPS. Toggles via T/t. SHIFT-f/F already used for frame-grab so don't want to mix things up.
• Make ui consistent for font, and color
• Make menus not be file names but try and parse out words. Remove extensions.
• Prevent UI from overlapping as much as possible when narrow.

Examples

Material labels	Geometry labels

With background	Without background

• UI overlap guards

Mobile	Desktop
Avoid menu items and label overwriting each other when narrow. Isn't really responsive but don't want to change current fixed formatting. (iPhone 12 Pro Sim)
Allow desktop to try and prevent overlap.