feat(stream): hash dispatcher: support multi columns

[fuyufjh]

What's changed and what's your intention?

as title

Checklist

• I have written necessary docs and comments
• I have added necessary unit tests and integration tests

Refer to a related PR or issue link (optional)

closes #210

[codecov]

Codecov Report

Merging #222 (7ed1bd1) into main (0b82d5f) will decrease coverage by 0.02%.
The diff coverage is 61.53%.

@@             Coverage Diff              @@
##               main     #222      +/-   ##
============================================
- Coverage     74.57%   74.55%   -0.03%     
- Complexity     2654     2656       +2     
============================================
  Files           839      839              
  Lines         47900    47933      +33     
  Branches       1562     1566       +4     
============================================
+ Hits          35721    35736      +15     
- Misses        11380    11397      +17     
- Partials        799      800       +1     

Flag	Coverage Δ
java	62.04% <0.00%> (-0.04%)	⬇️
rust	79.95% <66.66%> (-0.01%)	⬇️

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

Impacted Files	Coverage Δ
...ngwave/planner/rel/streaming/RwStreamExchange.java	59.72% <0.00%> (ø)
rust/meta/src/stream/graph/stream_graph.rs	86.95% <0.00%> (-3.96%)	⬇️
rust/meta/src/stream/test_fragmenter.rs	98.55% <ø> (ø)
rust/stream/src/task/test_mv.rs	100.00% <ø> (ø)
rust/stream/src/task/stream_manager.rs	52.35% <100.00%> (-0.12%)	⬇️
rust/stream/src/task/tests.rs	100.00% <100.00%> (ø)
...gwave/planner/planner/streaming/StreamPlanner.java	83.16% <0.00%> (-5.97%)	⬇️
rust/stream/src/task/barrier_manager.rs	93.25% <0.00%> (-1.06%)	⬇️
rust/storage/src/table/mview.rs	69.82% <0.00%> (-0.97%)	⬇️
...main/java/com/risingwave/catalog/TableCatalog.java	78.84% <0.00%> (-0.57%)	⬇️
... and 11 more

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