chore: Refactor FsFetchExecutorBuilder to handle rate limiting

[tabVersion]

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What's changed and what's your intention?

• Modify FsFetchExecutorBuilder to handle FlowControlExecutor
• Add rate limiting to FsFetchExecutor (the plan part is done here but left the exec part)

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• I have added fuzzing tests or opened an issue to track them. (Optional, recommended for new SQL features Sqlsmith: Sql feature generation #7934).
• My PR contains breaking changes. (If it deprecates some features, please create a tracking issue to remove them in the future).
• All checks passed in ./risedev check (or alias, ./risedev c)
• My PR changes performance-critical code. (Please run macro/micro-benchmarks and show the results.)

• My PR contains critical fixes that are necessary to be merged into the latest release. (Please check out the details)

Documentation

• My PR needs documentation updates. (Please use the Release note section below to summarize the impact on users)

Release note

If this PR includes changes that directly affect users or other significant modifications relevant to the community, kindly draft a release note to provide a concise summary of these changes. Please prioritize highlighting the impact these changes will have on users.

[tabVersion]

following #12595

[codecov]

Codecov Report

Merging #13006 (633e89f) into main (8b8c14c) will increase coverage by 0.08%.
Report is 4 commits behind head on main.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main   #13006      +/-   ##
==========================================
+ Coverage   68.71%   68.79%   +0.08%     
==========================================
  Files        1494     1494              
  Lines      250538   250542       +4     
==========================================
+ Hits       172152   172367     +215     
+ Misses      78386    78175     -211     

Flag	Coverage Δ
rust	68.79% <0.00%> (+0.08%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
src/stream/src/from_proto/source/fs_fetch.rs	0.00% <0.00%> (ø)

... and 19 files with indirect coverage changes

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