refactor(sync-execution): migrate agent result contract

[bobbai00]

What changes were proposed in this PR?

This is PR 1 of the split from #6009. It migrates the sync-execution backend and agent-service internals to the new execution summary contract while keeping the current frontend response shape compatible.

Core changes:

• Replace the sync-execution result model with WorkflowExecutionSummary, OperatorExecutionSummary, and OperatorResultSummary.
• Represent sampled rows as [rowIndex, Tuple] pairs instead of embedding row metadata into JSON result records.
• Reuse the shared WorkflowFatalError shape for execution and compilation-style failures.
• Update agent-service execution formatting, result cache, server paths, and tests to consume the new model.
• Keep GET /agents/:id/operator-results legacy-compatible through a temporary adapter, so the existing frontend continues to work until the follow-up frontend PR lands.

Main review files:

• amber/src/main/scala/org/apache/texera/web/resource/SyncExecutionResource.scala
• agent-service/src/types/execution.ts
• agent-service/src/server.ts

Any related issues, documentation, discussions?

Part of #5750.
Part of #5747.
Split from #6009.

A follow-up PR will migrate the frontend to consume the new summary shape directly and remove the temporary compatibility adapter.

How was this PR tested?

• cd agent-service && bun test src/server.spec.ts src/agent/tools/result-formatting.spec.ts src/agent/tools/tools-utility.spec.ts src/agent/tools/workflow-execution-tools.spec.ts src/agent/workflow-result-state.spec.ts
• cd agent-service && bun run format:check
• cd agent-service && bun run typecheck
• sbt scalafmtCheckAll

Attempted but did not complete locally:

• sbt "WorkflowExecutionService / testOnly org.apache.texera.web.resource.SyncExecutionResourceSpec"

The command failed before reaching the spec because local JOOQ generation could not authenticate to Postgres, then existing generated Java deprecation warnings hit -Werror during DAO / Compile.

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

Generated-by: Codex

[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.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 94.35484% with 7 lines in your changes missing coverage. Please review.
✅ Project coverage is 61.58%. Comparing base (1677e43) to head (ffaf65b).
⚠️ Report is 18 commits behind head on main.

Files with missing lines	Patch %	Lines
...he/texera/web/resource/SyncExecutionResource.scala	94.35%	6 Missing and 1 partial ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #6314      +/-   ##
============================================
+ Coverage     60.68%   61.58%   +0.90%     
- Complexity     3367     3444      +77     
============================================
  Files          1134     1134              
  Lines         44167    43950     -217     
  Branches       4827     4834       +7     
============================================
+ Hits          26802    27066     +264     
+ Misses        15907    15380     -527     
- Partials       1458     1504      +46     

Flag	Coverage Δ		*Carryforward flag
access-control-service	70.00% <ø> (ø)		Carriedforward from 1677e43
agent-service	44.23% <ø> (-0.37%)	⬇️	Carriedforward from 1677e43
amber	68.34% <94.35%> (+2.20%)	⬆️
computing-unit-managing-service	0.00% <ø> (ø)		Carriedforward from 1677e43
config-service	52.30% <ø> (ø)		Carriedforward from 1677e43
file-service	63.97% <ø> (ø)		Carriedforward from 1677e43
frontend	52.50% <ø> (ø)		Carriedforward from 1677e43
notebook-migration-service	78.57% <ø> (ø)		Carriedforward from 1677e43
pyamber	91.18% <ø> (ø)		Carriedforward from 1677e43
workflow-compiling-service	55.14% <ø> (ø)		Carriedforward from 1677e43

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

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[github-actions]

✅ No material benchmark regressions detected

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

Compared against main 1b42558 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	429	0.262	22,615/31,606/31,606 us	🟢 -8.8% / 🔴 +109.1%
🟢	bs=100 sw=10 sl=64	938	0.573	104,367/126,451/126,451 us	🟢 -10.7% / 🔴 +18.1%
⚪	bs=1000 sw=10 sl=64	1,113	0.68	897,113/941,193/941,193 us	⚪ within ±5% / 🟢 -11.0%

Baseline details

Latest main 1b42558 from same runner

config	metric	PR	latest main	7d avg	Δ latest	Δ 7d
bs=10 sw=10 sl=64	throughput	429 tuples/sec	429 tuples/sec	779.42 tuples/sec	0.0%	-45.0%
bs=10 sw=10 sl=64	MB/s	0.262 MB/s	0.262 MB/s	0.476 MB/s	0.0%	-44.9%
bs=10 sw=10 sl=64	p50	22,615 us	23,590 us	12,550 us	-4.1%	+80.2%
bs=10 sw=10 sl=64	p95	31,606 us	34,647 us	15,115 us	-8.8%	+109.1%
bs=10 sw=10 sl=64	p99	31,606 us	34,647 us	18,652 us	-8.8%	+69.5%
bs=100 sw=10 sl=64	throughput	938 tuples/sec	928 tuples/sec	1,000 tuples/sec	+1.1%	-6.2%
bs=100 sw=10 sl=64	MB/s	0.573 MB/s	0.566 MB/s	0.61 MB/s	+1.2%	-6.1%
bs=100 sw=10 sl=64	p50	104,367 us	102,539 us	99,872 us	+1.8%	+4.5%
bs=100 sw=10 sl=64	p95	126,451 us	141,556 us	107,073 us	-10.7%	+18.1%
bs=100 sw=10 sl=64	p99	126,451 us	141,556 us	114,377 us	-10.7%	+10.6%
bs=1000 sw=10 sl=64	throughput	1,113 tuples/sec	1,121 tuples/sec	1,020 tuples/sec	-0.7%	+9.1%
bs=1000 sw=10 sl=64	MB/s	0.68 MB/s	0.684 MB/s	0.622 MB/s	-0.6%	+9.2%
bs=1000 sw=10 sl=64	p50	897,113 us	896,636 us	987,499 us	+0.1%	-9.2%
bs=1000 sw=10 sl=64	p95	941,193 us	928,974 us	1,028,784 us	+1.3%	-8.5%
bs=1000 sw=10 sl=64	p99	941,193 us	928,974 us	1,057,136 us	+1.3%	-11.0%

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
0,10,10,64,20,466.09,200,128000,429,0.262,22615.32,31605.98,31605.98
1,100,10,64,20,2131.41,2000,1280000,938,0.573,104367.11,126450.87,126450.87
2,1000,10,64,20,17964.34,20000,12800000,1113,0.680,897112.58,941193.19,941193.19