Core: More SQL refactoring and tidying

[zach2good]

I affirm:

• [x] I understand that if I do not agree to the following points by completing the checkboxes my PR will be ignored.
• [x] I understand I should leave resolving conversations to the LandSandBoat team so that reviewers won't miss what was said.
• [x] I have read and understood the Contributing Guide and the Code of Conduct.
• [x] 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?

• More prepared stmts
• More multiple strings and not backslash broken strings
• Clean up LoadChar a bit
• Remove raw new from guilds
• Adds LIMIT 1 to a bunch of places

TODO

• [x] Remove _sql legacy handle
• [x] Remove sql.h/sql.cpp
• [x] Remove all "naked" queries for prepared statements
• [ ] Address all leftover TODOs, SQL->GetData() is popular here
• [ ] Make sure we aren't reusing rsets (const auto rset = ... only!)
• [ ] Audit all db::preparedStmts (530, or so) for %'s and proper use of rset
• [x] First-class support for enums in database, remove old support casting
• [x] Everything compiles again
• [ ] Log in, zone, form parties, send messages
• [ ] We're free of ALL Athena code!

[zach2good]

Optional extra: constexpr checks on preparedStmt to ensure they aren't using {} or %u/%s/%i etc.

[github-actions[bot]]

This PR has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[zach2good]

@sruon I think you've achieved everything I wanted to do in this PR? Did you also pick out the first-class enum support? If so this PR can be killed

[sruon]

I'll pull out the enum class part this week and then close it

[sruon]

Replaced by #8248