feat(pyamber): truncate range double keys

[carloea2]

What changes were proposed in this PR?

Python range shuffle now truncates finite double keys toward zero before bucket calculation, matching the JVM partitioner. Infinite values retain their existing endpoint routing.

Any related issues, documentation, discussions?

Closes #8255

How was this PR tested?

python -c "import sys,pytest; sys.path[:0]=[r'C:\Users\carlo\texera\texera-worktrees\investigate-bug64\amber\src\main\python',r'C:\Users\carlo\texera\texera\amber\src\main\python']; raise SystemExit(pytest.main(['amber/src/test/python/core/architecture/sendsemantics/test_partitioners.py','-q','-p','no:cacheprovider']))"
38 passed

ruff check amber/src/main/python amber/src/test/python
All checks passed

ruff format --check amber/src/main/python amber/src/test/python
213 files already formatted

Direct reproduction after the fix:

receiver=B truncated_index=1

Was this PR authored or co-authored using generative AI tooling?

Generated-by: Codex

[github-actions]

Backport auto-label report

This fix: PR was checked against each actively-supported release branch. release/* labels drive the post-merge backport, so add or remove one to change where this fix lands.

Release branch	Analysis
⚠️ release/v1.3	Not labeled automatically — none of the files this PR modifies exist on this branch (amber/src/main/python/core/architecture/sendsemantics/range_based_shuffle_partitioner.py, amber/src/test/python/core/architecture/sendsemantics/test_partitioners.py). The fix may target code that isn't on this release, or the files were moved/renamed after the branch was cut. Please check and add release/v1.3 by hand if this fix should be backported here.
✅ release/v1.2	Already labeled — this fix is queued to backport here.

Auto-label run.

[github-actions]

Automated Reviewer Suggestions

Based on the git blame history of the changed files, we recommend the following reviewers:

• Contributors with relevant context: @Ma77Ball, @Yicong-Huang
  You can notify them by mentioning @Ma77Ball, @Yicong-Huang in a comment.

[github-actions]

⚠️ Benchmark changes need a look

🟢 2 better · 🔴 2 worse · ⚪ 11 noise (<±5%) · 0 without baseline

Compared against main 50321e4 benchmarked on this same runner, so the delta is largely free of cross-runner hardware noise. The "7d avg" column still reflects the gh-pages dashboard. Treat <±5% as noise unless repeated.

Dashboard · Run

	config	throughput	MB/s	latency	max Δ latest / 7d
🔴	bs=10 sw=10 sl=64	420	0.257	23,059/29,121/29,121 us	🔴 -10.3% / 🔴 +86.9%
🟢	bs=100 sw=10 sl=64	949	0.579	105,590/123,923/123,923 us	🟢 -14.9% / 🔴 +15.6%
⚪	bs=1000 sw=10 sl=64	1,078	0.658	928,554/1,002,764/1,002,764 us	⚪ within ±5% / 🟢 -5.4%

Baseline details

Latest main 50321e4 from same runner

config	metric	PR	latest main	7d avg	Δ latest	Δ 7d
bs=10 sw=10 sl=64	throughput	420 tuples/sec	468 tuples/sec	787.98 tuples/sec	-10.3%	-46.7%
bs=10 sw=10 sl=64	MB/s	0.257 MB/s	0.286 MB/s	0.481 MB/s	-10.1%	-46.6%
bs=10 sw=10 sl=64	p50	23,059 us	22,434 us	12,593 us	+2.8%	+83.1%
bs=10 sw=10 sl=64	p95	29,121 us	28,058 us	15,579 us	+3.8%	+86.9%
bs=10 sw=10 sl=64	p99	29,121 us	28,058 us	18,786 us	+3.8%	+55.0%
bs=100 sw=10 sl=64	throughput	949 tuples/sec	931 tuples/sec	1,008 tuples/sec	+1.9%	-5.8%
bs=100 sw=10 sl=64	MB/s	0.579 MB/s	0.568 MB/s	0.615 MB/s	+1.9%	-5.9%
bs=100 sw=10 sl=64	p50	105,590 us	102,003 us	100,701 us	+3.5%	+4.9%
bs=100 sw=10 sl=64	p95	123,923 us	145,609 us	107,244 us	-14.9%	+15.6%
bs=100 sw=10 sl=64	p99	123,923 us	145,609 us	116,122 us	-14.9%	+6.7%
bs=1000 sw=10 sl=64	throughput	1,078 tuples/sec	1,095 tuples/sec	1,042 tuples/sec	-1.6%	+3.5%
bs=1000 sw=10 sl=64	MB/s	0.658 MB/s	0.669 MB/s	0.636 MB/s	-1.6%	+3.5%
bs=1000 sw=10 sl=64	p50	928,554 us	915,115 us	981,959 us	+1.5%	-5.4%
bs=1000 sw=10 sl=64	p95	1,002,764 us	956,740 us	1,023,080 us	+4.8%	-2.0%
bs=1000 sw=10 sl=64	p99	1,002,764 us	956,740 us	1,051,697 us	+4.8%	-4.7%

Raw CSV

config_idx,batch_size,schema_width,string_len,num_batches,total_ms,total_tuples,total_bytes,tuples_per_sec,mb_per_sec,lat_p50_us,lat_p95_us,lat_p99_us
0,10,10,64,20,475.81,200,128000,420,0.257,23058.61,29120.74,29120.74
1,100,10,64,20,2108.49,2000,1280000,949,0.579,105589.61,123923.46,123923.46
2,1000,10,64,20,18550.21,20000,12800000,1078,0.658,928553.74,1002764.00,1002764.00

[Yicong-Huang]

I am converting this PR to a draft: please follow our PR template and mark it ready for review.

[carloea2]

The description now follows the current template, and this is ready for review.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.90%. Comparing base (50321e4) to head (2a56d2d).
⚠️ Report is 11 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #8256      +/-   ##
============================================
- Coverage     93.93%   93.90%   -0.04%     
+ Complexity     4762     4761       -1     
============================================
  Files          1191     1191              
  Lines         48308    49053     +745     
  Branches       5377     5377              
============================================
+ Hits          45380    46061     +681     
- Misses         1494     1557      +63     
- Partials       1434     1435       +1     

Flag	Coverage Δ		*Carryforward flag
access-control-service	81.00% <ø> (ø)		Carriedforward from 50321e4
agent-service	99.32% <ø> (ø)		Carriedforward from 50321e4
amber	90.02% <ø> (-0.02%)	⬇️	Carriedforward from 50321e4
computing-unit-managing-service	73.67% <ø> (ø)		Carriedforward from 50321e4
config-service	86.86% <ø> (ø)		Carriedforward from 50321e4
file-service	87.91% <ø> (ø)		Carriedforward from 50321e4
frontend	96.41% <ø> (ø)		Carriedforward from 50321e4
notebook-migration-service	79.31% <ø> (ø)		Carriedforward from 50321e4
pyamber	97.87% <100.00%> (-1.00%)	⬇️
workflow-compiling-service	77.19% <ø> (ø)		Carriedforward from 50321e4

*This pull request uses carry forward flags. Click here to find out more.

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