feat(streaming): persist row_count in backfill state_table

[kwannoel]

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What's changed and what's your intention?

We have to persist the back-filled row count somehow, so that after recovery we can still report the ddl progress.
We store it in the backfill's state_table in this PR, and recover it from there as well.

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
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[codecov]

Codecov Report

Merging #12415 (f4a55c8) into main (c9b356a) will decrease coverage by 0.02%.
Report is 20 commits behind head on main.
The diff coverage is 10.34%.

@@            Coverage Diff             @@
##             main   #12415      +/-   ##
==========================================
- Coverage   69.61%   69.60%   -0.02%     
==========================================
  Files        1424     1424              
  Lines      236554   236608      +54     
==========================================
+ Hits       164677   164683       +6     
- Misses      71877    71925      +48     

Flag	Coverage Δ
rust	69.60% <10.34%> (-0.02%)	⬇️

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

Files Changed	Coverage Δ
...tream/src/executor/backfill/no_shuffle_backfill.rs	0.00% <0.00%> (ø)
src/stream/src/executor/backfill/utils.rs	8.82% <0.00%> (-0.76%)	⬇️
src/stream/src/task/barrier_manager/progress.rs	54.92% <ø> (ø)
...ntend/src/optimizer/plan_node/stream_table_scan.rs	98.64% <100.00%> (+0.03%)	⬆️

... and 2 files with indirect coverage changes

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[chenzl25]

LGTM