[core] Map>Packets>Various A thru M files: Russian to English

[EpicTaru]

I affirm:

• I understand that if I do not agree to the following points by completing the checkboxes my PR will be ignored.
• I understand I should leave resolving conversations to the LandSandBoat team so that reviewers won't miss what was said.
• I have read and understood the Contributing Guide and the Code of Conduct.
• I have tested my code and the things my code has changed since the last commit in the PR and will test after any later commits.

What does this pull request do?

Within /src/map/packets/:
char_jobs.cpp,
char_stats.cpp,
inventory_assign.h,
keyitems.h,
merit_points_categories.cpp,
message_text.cpp

• Translated Russian comments to English
• Removed any un-necessary/non-helpful translations/empty comment blocks
  • If more are deemed un-necessary/non-helpful/if I was too strict in my removals, please let me know!
• Corrected grammar/formatting of any pre-existing comments that I came across during the above processing

Steps to test these changes

No testing necessary, no code was changed, only comments.

[EpicTaru]

не помню, зачем я сунул это сюда = I don't remember why I put this here