Fix the alignment of many unicode strings

[Qrox]

Summary

SUMMARY: Interface "Assorted string alignment fixes"

Purpose of change

Fix the incorrect alignment of many strings when they contain unicode characters.

Describe the solution

Used utf8_width instead of string::size/length to calculate the display width of strings. Three new functions left_justify, right_justify, and utf8_justify were added and used instead of %<num>s to correctly handle the left/right justifying of utf8 strings.

Replaced some string::size/length calls used for emptyness check/access to the last element with string::empty/back.

Also fixed a bunch of small bugs/issues I encountered when testing the changes:

1. Player with debug hammerspace can now immediately finish any faction camp missions to make debugging with the faction camp code easier.
2. Used the non-breaking space (0xA0) after item health bars to make NPC clothing description in the look-around mode prettier.
3. Fixed the issue where unicode characters inside scrolling combat text were not displayed.

Testing

All fixes were tested in-game and were working as expected.