feat(amber): set cache-control headers for static frontend assets

[Ma77Ball]

What changes were proposed in this PR?

• Add StaticAssetCacheFilter, registered on /* in TexeraWebApplication, that sets Cache-Control on static frontend responses by request path.
• index.html, the root, and Angular route paths get no-cache, must-revalidate so a stale entry document is never served past a deploy; content-hashed bundles (name..js/.css and other fingerprinted assets) get public, max-age=31536000, immutable; /api/* responses are left untouched.
• The Cache-Control decision lives in a pure StaticAssetCacheFilter.cacheControlFor(path) function so it is unit-testable without a servlet container.

Any related issues, documentation, discussions?

Closes: #5835

How was this PR tested?

• Run sbt "WorkflowExecutionService/testOnly *StaticAssetCacheFilterSpec" on JDK 17, expect 7 passing cases: hashed js/css/media to immutable, index.html and Angular routes to revalidate, /api/* untouched, and short numeric segments not mistaken for a content hash.
• Manual: build the frontend, start dashboard-service, run curl -I http://localhost:8080/index.html and expect Cache-Control: no-cache, must-revalidate; curl -I a hashed bundle (e.g. /main..js) and expect Cache-Control: public, max-age=31536000, immutable.
• The servlet registration in TexeraWebApplication.run is covered by the manual curl steps, not the unit spec (the spec covers the header-decision logic).

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

Co-authored with Claude Opus 4.8 in compliance with ASF

[github-actions]

⚠️ Benchmark changes need a look

🟢 2 better · 🔴 7 worse · ⚪ 6 noise (<±5%) · 0 without baseline

Compared against main 6eb4165 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	403	0.246	24,052/31,349/31,349 us	🔴 -7.4% / 🟢 -10.4%
🔴	bs=100 sw=10 sl=64	822	0.502	119,526/148,059/148,059 us	🔴 +19.1% / 🔴 -7.8%
⚪	bs=1000 sw=10 sl=64	944	0.576	1,062,736/1,085,949/1,085,949 us	⚪ within ±5% / 🔴 -9.3%

Baseline details

Latest main 6eb4165 from same runner

config	metric	PR	latest main	7d avg	Δ latest	Δ 7d
bs=10 sw=10 sl=64	throughput	403 tuples/sec	435 tuples/sec	410.82 tuples/sec	-7.4%	-1.9%
bs=10 sw=10 sl=64	MB/s	0.246 MB/s	0.265 MB/s	0.251 MB/s	-7.2%	-1.9%
bs=10 sw=10 sl=64	p50	24,052 us	22,887 us	23,785 us	+5.1%	+1.1%
bs=10 sw=10 sl=64	p95	31,349 us	33,479 us	34,980 us	-6.4%	-10.4%
bs=10 sw=10 sl=64	p99	31,349 us	33,479 us	34,980 us	-6.4%	-10.4%
bs=100 sw=10 sl=64	throughput	822 tuples/sec	871 tuples/sec	891.94 tuples/sec	-5.6%	-7.8%
bs=100 sw=10 sl=64	MB/s	0.502 MB/s	0.531 MB/s	0.544 MB/s	-5.5%	-7.8%
bs=100 sw=10 sl=64	p50	119,526 us	114,220 us	112,277 us	+4.6%	+6.5%
bs=100 sw=10 sl=64	p95	148,059 us	124,355 us	139,802 us	+19.1%	+5.9%
bs=100 sw=10 sl=64	p99	148,059 us	124,355 us	139,802 us	+19.1%	+5.9%
bs=1000 sw=10 sl=64	throughput	944 tuples/sec	932 tuples/sec	1,041 tuples/sec	+1.3%	-9.3%
bs=1000 sw=10 sl=64	MB/s	0.576 MB/s	0.569 MB/s	0.635 MB/s	+1.2%	-9.3%
bs=1000 sw=10 sl=64	p50	1,062,736 us	1,075,520 us	972,714 us	-1.2%	+9.3%
bs=1000 sw=10 sl=64	p95	1,085,949 us	1,107,212 us	1,023,057 us	-1.9%	+6.1%
bs=1000 sw=10 sl=64	p99	1,085,949 us	1,107,212 us	1,023,057 us	-1.9%	+6.1%

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
0,10,10,64,20,496.27,200,128000,403,0.246,24051.75,31348.63,31348.63
1,100,10,64,20,2431.99,2000,1280000,822,0.502,119525.99,148059.24,148059.24
2,1000,10,64,20,21178.18,20000,12800000,944,0.576,1062735.67,1085948.95,1085948.95

[codecov-commenter]

Codecov Report

❌ Patch coverage is 73.91304% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 54.32%. Comparing base (6eb4165) to head (b90cf72).
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
...a/org/apache/texera/web/TexeraWebApplication.scala	0.00%	4 Missing ⚠️
...org/apache/texera/web/StaticAssetCacheFilter.scala	89.47%	0 Missing and 2 partials ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #5846      +/-   ##
============================================
- Coverage     54.42%   54.32%   -0.11%     
+ Complexity     2891     2890       -1     
============================================
  Files          1107     1103       -4     
  Lines         42768    42635     -133     
  Branches       4599     4588      -11     
============================================
- Hits          23276    23160     -116     
+ Misses        18130    18120      -10     
+ Partials       1362     1355       -7     

Flag	Coverage Δ		*Carryforward flag
access-control-service	70.44% <ø> (ø)		Carriedforward from ed22158
agent-service	34.36% <ø> (ø)		Carriedforward from ed22158
amber	56.34% <73.91%> (+0.03%)	⬆️
computing-unit-managing-service	1.65% <ø> (ø)		Carriedforward from ed22158
config-service	57.35% <ø> (ø)		Carriedforward from ed22158
file-service	57.36% <ø> (-1.24%)	⬇️	Carriedforward from ed22158
frontend	48.02% <ø> (-0.26%)	⬇️	Carriedforward from ed22158
pyamber	90.15% <ø> (-0.05%)	⬇️	Carriedforward from ed22158
python	90.76% <ø> (ø)		Carriedforward from ed22158
workflow-compiling-service	58.69% <ø> (ø)		Carriedforward from ed22158

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

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[github-actions]

Automated Reviewer Suggestions

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

• Contributors with relevant context: @aicam
  You can notify them by mentioning @aicam in a comment.

[Ma77Ball]

/request-review @Yicong-Huang