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

🟢 6 better · 🔴 3 worse · ⚪ 6 noise (<±5%) · 0 without baseline

Compared against main 6db0d6b 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	410	0.25	23,737/30,798/30,798 us	🔴 -7.1% / 🔴 +97.7%
🟢	bs=100 sw=10 sl=64	838	0.511	119,037/130,878/130,878 us	🟢 -19.2% / 🔴 +19.4%
⚪	bs=1000 sw=10 sl=64	929	0.567	1,077,839/1,104,452/1,104,452 us	⚪ within ±5% / 🔴 -6.8%

Baseline details

Latest main 6db0d6b from same runner

config	metric	PR	latest main	7d avg	Δ latest	Δ 7d
bs=10 sw=10 sl=64	throughput	410 tuples/sec	441 tuples/sec	758.88 tuples/sec	-7.0%	-46.0%
bs=10 sw=10 sl=64	MB/s	0.25 MB/s	0.269 MB/s	0.463 MB/s	-7.1%	-46.0%
bs=10 sw=10 sl=64	p50	23,737 us	22,385 us	12,965 us	+6.0%	+83.1%
bs=10 sw=10 sl=64	p95	30,798 us	32,557 us	15,578 us	-5.4%	+97.7%
bs=10 sw=10 sl=64	p99	30,798 us	32,557 us	18,378 us	-5.4%	+67.6%
bs=100 sw=10 sl=64	throughput	838 tuples/sec	789 tuples/sec	968.9 tuples/sec	+6.2%	-13.5%
bs=100 sw=10 sl=64	MB/s	0.511 MB/s	0.482 MB/s	0.591 MB/s	+6.0%	-13.6%
bs=100 sw=10 sl=64	p50	119,037 us	120,352 us	102,767 us	-1.1%	+15.8%
bs=100 sw=10 sl=64	p95	130,878 us	162,019 us	109,629 us	-19.2%	+19.4%
bs=100 sw=10 sl=64	p99	130,878 us	162,019 us	118,129 us	-19.2%	+10.8%
bs=1000 sw=10 sl=64	throughput	929 tuples/sec	936 tuples/sec	997.01 tuples/sec	-0.7%	-6.8%
bs=1000 sw=10 sl=64	MB/s	0.567 MB/s	0.571 MB/s	0.609 MB/s	-0.7%	-6.8%
bs=1000 sw=10 sl=64	p50	1,077,839 us	1,066,572 us	1,009,306 us	+1.1%	+6.8%
bs=1000 sw=10 sl=64	p95	1,104,452 us	1,103,494 us	1,051,088 us	+0.1%	+5.1%
bs=1000 sw=10 sl=64	p99	1,104,452 us	1,103,494 us	1,082,535 us	+0.1%	+2.0%

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
0,10,10,64,20,487.59,200,128000,410,0.250,23736.75,30798.38,30798.38
1,100,10,64,20,2387.50,2000,1280000,838,0.511,119037.10,130877.69,130877.69
2,1000,10,64,20,21536.23,20000,12800000,929,0.567,1077838.59,1104452.44,1104452.44

[codecov-commenter]

Codecov Report

❌ Patch coverage is 73.91304% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 55.17%. Comparing base (6db0d6b) to head (390791f).
✅ 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     55.19%   55.17%   -0.02%     
+ Complexity     2978     2976       -2     
============================================
  Files          1117     1118       +1     
  Lines         43195    43218      +23     
  Branches       4657     4661       +4     
============================================
+ Hits          23840    23847       +7     
- Misses        17955    17964       +9     
- Partials       1400     1407       +7     

Flag	Coverage Δ		*Carryforward flag
access-control-service	70.00% <ø> (ø)		Carriedforward from 6db0d6b
agent-service	34.36% <ø> (ø)		Carriedforward from 6db0d6b
amber	57.62% <73.91%> (-0.04%)	⬇️
computing-unit-managing-service	0.00% <ø> (ø)		Carriedforward from 6db0d6b
config-service	51.56% <ø> (ø)		Carriedforward from 6db0d6b
file-service	59.02% <ø> (ø)		Carriedforward from 6db0d6b
frontend	48.77% <ø> (ø)		Carriedforward from 6db0d6b
notebook-migration-service	78.57% <ø> (ø)		Carriedforward from 6db0d6b
pyamber	90.20% <ø> (ø)		Carriedforward from 6db0d6b
python	90.76% <ø> (ø)		Carriedforward from 6db0d6b
workflow-compiling-service	55.14% <ø> (ø)		Carriedforward from 6db0d6b

*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

[Ma77Ball]

/request-review @aglinxinyuan