refactor(optimizer): rename logical pk to stream key

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What's changed and what's your intention?

a part of #12514

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

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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.

[codecov]

Codecov Report

Merging #12516 (fd4f89f) into main (063f58e) will increase coverage by 0.01%.
Report is 5 commits behind head on main.
The diff coverage is 69.44%.

@@            Coverage Diff             @@
##             main   #12516      +/-   ##
==========================================
+ Coverage   69.41%   69.43%   +0.01%     
==========================================
  Files        1429     1429              
  Lines      238590   238590              
==========================================
+ Hits       165621   165660      +39     
+ Misses      72969    72930      -39     

Flag	Coverage Δ
rust	69.43% <69.44%> (+0.01%)	⬆️

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

Files Changed	Coverage Δ
...rc/frontend/src/optimizer/plan_node/generic/mod.rs	30.00% <0.00%> (ø)
...frontend/src/optimizer/plan_node/generic/update.rs	63.15% <0.00%> (ø)
.../frontend/src/optimizer/plan_node/stream_derive.rs	0.00% <0.00%> (ø)
src/frontend/src/optimizer/plan_node/stream.rs	13.81% <12.50%> (ø)
src/frontend/src/optimizer/plan_node/derive.rs	97.43% <100.00%> (ø)
...rc/frontend/src/optimizer/plan_node/generic/agg.rs	91.88% <100.00%> (ø)
.../frontend/src/optimizer/plan_node/generic/dedup.rs	100.00% <100.00%> (ø)
...frontend/src/optimizer/plan_node/generic/delete.rs	100.00% <100.00%> (ø)
.../src/optimizer/plan_node/generic/dynamic_filter.rs	96.85% <100.00%> (ø)
...frontend/src/optimizer/plan_node/generic/except.rs	81.25% <100.00%> (ø)
... and 42 more

... and 6 files with indirect coverage changes

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