Alias manual -> instruction manual

BUR #52265 has been approved by @nonamethanks.

rename manual -> instruction_manual

Seems to be a redundant tag.

Shouldn’t we deprecate manual as well?

They're mutually exclusive, it's one or the other. Deprecated tags can't have aliases.

An alias means trying to add the former tag will automatically change it to the latter. For all practical purposes, the former tag is merged into the latter.

This is different from a rename, which simply edits all posts with the old tag to the new one (as well as the corresponding wiki page and any links), but the old tag still remains as a separate tag.

The bulk update request #52265 (forum #405311) has been approved by @nonamethanks.

Changed to a rename. Anyone writing "manual" will already get this suggested to them.