DAOS-18527 cart: Handling of string env limits (#17466)

[frostedcmos]

• CRT_ENV_STR_MAX_SIZE introduced, set to 1024. All string envs are checked against this limit at the data_init() time.

• Additional checks added for domain/interface not to exceed this limit, as those can be passed via crt_init_opt.

Steps for the author:

• Commit message follows the guidelines.
• Appropriate Features or Test-tag pragmas were used.
• Appropriate Functional Test Stages were run.
• At least two positive code reviews including at least one code owner from each category referenced in the PR.
• Testing is complete. If necessary, forced-landing label added and a reason added in a comment.

After all prior steps are complete:

• Gatekeeper requested (daos-gatekeeper added as a reviewer).

[github-actions]

Ticket title is 'CART: cart limits interface/domain strings to 64 characters, resulting in errors'
Status is 'In Progress'
Labels: 'request_for_2.6.6'
https://daosio.atlassian.net/browse/DAOS-18527