Cleanup: comment bone cycling & simplify logic

Fix menu search referencing image menu

In this case it was called mask which wasn't correct since it's
used for image & UV's, so rename the menu instead.

Cleanup: unused variable

Fix T75425: Bone selection cycling not working

Edit-mode bone selection now cycles on successive clicks.
This now cycles through multiple edit-objects & bones.

Cleanup: rename to BLI_path_cwd to BLI_path_abs_from_cwd

This is now more clearly a function that makes the path absolute
using the current working directory.

Cleanup: missed renaming BLI_cleanup_unc_16 in recent refactor

Missed from d14e76806921f

Cleanup: reduce scope of variables in custom data copying

Fix T67098: Inset causes shape keys to reset exiting edit-mode

Edit-mesh interactive redo reset the meshes shape-key index.

Also copy the selection mode when copying meshes.

Cleanup: disable clang-format for character table

Fix status bar message showing saved when saving failed

Resolves the following issues:

- For the first time you save a .blend file, there was no feedback.
- If the file fails to save (eg "No space left on device") the status
bar message replaces the error with an invalid "Saved" message.

While there is a popup, the user may cancel it with mouse motion
and be left with the status bar message saying the file saved.

D7371 by @XDroid with edits.