feat(stream): introduce relational top_n

[wcy-fdu]

What's changed and what's your intention?

This PR Implements the read/write of TopN executor by state table, which removed flush_buffer in top_n_state and top_n_bottom_n_state.
Since top_n has implemented a merge logic of flush_buffer and storage named scan_and_merge, I just refactor it and rename to scan from relational_table (Or we can change it to something more appropriate).

Checklist

• I have written necessary docs and comments
• I have added necessary unit tests and integration tests
• All checks passed in ./risedev check (or alias, ./risedev c)

Refer to a related PR or issue link (optional)

close #1206

[codecov]

Codecov Report

Merging #3160 (d3d6ff3) into main (46d5477) will decrease coverage by 0.03%.
The diff coverage is 87.34%.

@@            Coverage Diff             @@
##             main    #3160      +/-   ##
==========================================
- Coverage   73.55%   73.51%   -0.04%     
==========================================
  Files         745      744       -1     
  Lines      101501   101354     -147     
==========================================
- Hits        74659    74514     -145     
+ Misses      26842    26840       -2     

Flag	Coverage Δ
rust	73.51% <87.34%> (-0.04%)	⬇️

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

Impacted Files	Coverage Δ
src/stream/src/executor/mview/materialize.rs	89.28% <ø> (ø)
src/storage/src/table/cell_based_table.rs	71.67% <54.54%> (+0.24%)	⬆️
...ecutor/managed_state/top_n/top_n_bottom_n_state.rs	82.70% <64.15%> (+5.07%)	⬆️
src/storage/src/table/state_table.rs	83.49% <82.60%> (+0.73%)	⬆️
...am/src/executor/managed_state/top_n/top_n_state.rs	93.52% <94.64%> (+0.49%)	⬆️
src/common/src/util/ordered/serde.rs	89.10% <100.00%> (-2.53%)	⬇️
src/storage/src/table/test_relational_table.rs	98.07% <100.00%> (ø)
...am/src/executor/managed_state/aggregation/value.rs	94.30% <100.00%> (ø)
src/stream/src/executor/mview/test_utils.rs	100.00% <100.00%> (ø)
src/stream/src/executor/top_n.rs	91.47% <100.00%> (-0.12%)	⬇️
... and 9 more

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[lmatz]

LGTM!