MDEV-35856: implement index hints

[Olernov]

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• [x] The Jira issue number for this PR is: MDEV-35856

Description

This commit implements optimizer hints affecting the use of indexes:

• ORDER_INDEX, NO_ORDER_INDEX
• GROUP_INDEX, NO_GROUP_INDEX
• JOIN_INDEX, NO_JOIN_INDEX
• INDEX, NO_INDEX

How can this PR be tested?

./mtr opt_hints_index

If the changes are not amenable to automated testing, please explain why not and carefully describe how to test manually.

Basing the PR against the correct MariaDB version

• [x] This is a new feature or a refactoring, and the PR is based against the main branch.
• [ ] This is a bug fix, and the PR is based against the earliest maintained branch in which the bug can be reproduced.

PR quality check

• [x] I checked the CODING_STANDARDS.md file and my PR conforms to this where appropriate.
• [x] For any trivial modifications to the PR, I am ok with the reviewer making the changes themselves.