fix!: replace timeout_millis and connect_timeout_millis with Duration in DatanodeClientOptions

[WenyXu]

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What's changed and what's your intention?

Updated DatanodeClientOptions to use Duration for timeout and connect_timeout with humantime_serde serialization.
Modified MetasrvBuilder to use the updated DatanodeClientOptions.

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.

[codecov]

Codecov Report

Attention: Patch coverage is 77.77778% with 2 lines in your changes missing coverage. Please review.

Project coverage is 83.99%. Comparing base (6d503b0) to head (404a525).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4867      +/-   ##
==========================================
- Coverage   84.25%   83.99%   -0.27%     
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  Files        1129     1129              
  Lines      208474   208474              
==========================================
- Hits       175653   175101     -552     
- Misses      32821    33373     +552