chore(rpc): set message size to max for stream client

[zwang28]

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What's changed and what's your intention?

The response of barrier_complete RPC can be very large due to synced_sstables field, which is mostly compromised of large storage keys.

For example, this source can reproduce a large response size failing the barrier collection.

create table t_large_key (k varchar, v int, primary key(k)) with (
    connector = 'datagen',
    fields.k.length = 4194304,
    datagen.rows.per.second='1',
    datagen.split.num = '1'
);

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).
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Documentation

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Release note

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[codecov]

Codecov Report

Merging #12082 (12bbb38) into main (ff623ee) will decrease coverage by 0.02%.
Report is 6 commits behind head on main.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main   #12082      +/-   ##
==========================================
- Coverage   69.81%   69.80%   -0.02%     
==========================================
  Files        1402     1402              
  Lines      234730   234732       +2     
==========================================
- Hits       163888   163855      -33     
- Misses      70842    70877      +35     

Flag	Coverage Δ
rust	69.80% <100.00%> (-0.02%)	⬇️

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Files Changed	Coverage Δ
src/rpc_client/src/stream_client.rs	100.00% <100.00%> (ø)

... and 9 files with indirect coverage changes

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