More variety in the chat "thinking" indicator

The loading indicator shown while the assistant is working now cycles through a much larger pool of whimsical verbs (Ruminating, Sleuthing, Triangulating, Spelunking, "Connecting the dots", and more), so it repeats far less often during longer waits.

Features

Expand the "thinking" verb pool #3449 - The chat loading indicator draws from a much larger set of whimsical "thinking" verbs while the assistant is working, cutting down on repetition. (Author: @adaam2)