Add SSL/TLS version to status output

[rolandwalker]

Description

Checklist

• I added this contribution to the changelog.md file.
• I added my name to the AUTHORS file (or it's already there).
• To lint and format the code, I ran

  uv run ruff check && uv run ruff format && uv run mypy --install-types .

[github-actions]

Findings (by severity)

1. Correctness: global SSL version cache can return wrong values across connections.
   get_ssl_version caches a single value in CACHED_SSL_VERSION for the entire process, but status is per-connection. If the first call is against a non-SSL session (or a server that doesn’t expose Ssl_version), subsequent calls for other connections will always show None, even if they are SSL-enabled. This is a regression for multi-connection workflows or reconnects.
   Path: mycli/packages/special/utils.py
   Action: remove the cache, or key the cache by connection identity (e.g., cur.connection.thread_id() plus host/port), and allow recalc when the connection changes.

2. Correctness: cache “no row” sentinel permanently hides SSL version on other servers.
   When no row is returned, the cache is set to '', so future calls never requery. If you connect to an older server first and then to a newer one, you’ll never display the SSL version.
   Path: mycli/packages/special/utils.py
   Action: same as above—avoid global cache or tie it to the connection.

Missing tests / edge cases

• Add tests for get_ssl_version / status output:
  • SSL-enabled session returns a version.
  • Non-SSL / no-row returns None (or desired placeholder).
  • Ensure values don’t leak across separate connection instances.
    Suggested location: test/test_dbspecial.py or a new test alongside existing special/dbcommands tests.

Notes

• I didn’t run tests locally. If you want, I can add the tests and adjust the caching logic.

Possible next steps

1. Remove or scope the SSL version cache per connection.
2. Add unit tests for SSL version reporting (including cross-connection behavior).

[scottnemes]

Verified SSL version is shown when connected via SSL, and that <null> is shown when connected without SSL.