feat(samples): [Cache Tracing 4] Add cache tracing e2e sample

[adinauer]

PR Stack (Cache Tracing)

• #5162 — Add SentryCacheWrapper and SentryCacheManagerWrapper
• #5163 — Add enableCacheTracing option
• #5164 — Add BeanPostProcessor and auto-configuration
• #5167 — Add cache tracing e2e sample

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📜 Description

Adds an e2e sample and system test for cache tracing in the Spring Boot 4 sample app.

• Enables @EnableCaching with ConcurrentMapCacheManager (in-memory, no Redis needed)
• Adds TodoService with @Cacheable, @CachePut, @CacheEvict annotations
• Adds CacheController with REST endpoints (GET/POST/DELETE /cache/)
• Adds RestTestClient methods for cache endpoints
• Adds CacheSystemTest verifying cache.put, cache.get, and cache.remove spans

💡 Motivation and Context

Demonstrates the cache tracing feature end-to-end and provides system test coverage.

💚 How did you test it?

• System test CacheSystemTest exercises all cache operations and asserts spans are received by the mock Sentry server

📝 Checklist

• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• No breaking change or entry added to the changelog.

🔮 Next steps

None — this completes the cache tracing stack.

#skip-changelog

[github-actions]

Semver Impact of This PR

🟡 Minor (new features)

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[github-actions]

	Messages
📖	Do not forget to update Sentry-docs with your feature once the pull request gets approved.

Generated by 🚫 dangerJS against 89b88b0

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	338.62 ms	376.54 ms	37.92 ms
Size	0 B	0 B	0 B

Baseline results on branch: feat/cache-tracing-autoconfig

Startup times

Revision	Plain	With Sentry	Diff
ad651f5	362.86 ms	440.44 ms	77.57 ms
97c5869	356.91 ms	456.61 ms	99.70 ms
9071b35	318.77 ms	372.18 ms	53.41 ms

App size

Revision	Plain	With Sentry	Diff
ad651f5	1.58 MiB	2.29 MiB	723.27 KiB
97c5869	0 B	0 B	0 B
9071b35	1.58 MiB	2.29 MiB	722.92 KiB