enhance : update vector index defeault value

[foxspy]

issue : milvus-io/milvus#36906
Discussed with product manager, we need give default value for most index params. The document will be updated together

[sre-ci-robot]

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[mergify]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 74.29%. Comparing base (3c46f4c) to head (3cde26b).
Report is 251 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff            @@
##           main     #946       +/-   ##
=========================================
+ Coverage      0   74.29%   +74.29%     
=========================================
  Files         0       82       +82     
  Lines         0     6644     +6644     
=========================================
+ Hits          0     4936     +4936     
- Misses        0     1708     +1708     

see 82 files with indirect coverage changes

[foxspy]

/kind improvement

[chasingegg]

/lgtm