chore: replace resilience dep with zero-dependency native impl

[swaldmann]

@sap-cloud-sdk/resilience is basically a wrapper around async-retry, last updated 5 years ago.

This PR removes @sap-cloud-sdk/resilience and replaces timeout, retry, and circuitBreaker with a Node-native, zero dependencies implementation.

AbortController is now wired into the request signal so timeouts actually cancel the in-flight HTTP call instead of just ignoring it. Retry uses capped exponential backoff (32 seconds max) with jitter.

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• Added relevant entry to the change log?

[schiwekM]

Nice, could you add it to the anthropic model as well?

[hyperspace-pr-bot]

Summary

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Chore: Replace @sap-cloud-sdk/resilience with Zero-Dependency Native Implementation

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• Added relevant entry to the change log?

Overview

This PR removes the @sap-cloud-sdk/resilience dependency (a wrapper around async-retry, last updated 5 years ago) and replaces it with a Node-native, zero-dependency implementation of timeout, retry, and circuitBreaker resilience patterns.

Changes

New lib/utils/resilience.js

A self-contained resilience module implementing three middleware functions:

• timeout(ms) — Wires AbortController into the request signal so timeouts actually cancel the in-flight HTTP call. Uses Promise.race against a timer that aborts the underlying request.
• retry(retries) — Capped exponential backoff (max 32s) with jitter. Bails immediately on 4xx errors; retries on 5xx and network errors.
• circuitBreaker() — Per-URI breaker with a rolling time window. Opens after volume threshold calls exceed the error rate; fails fast with EOPENBREAKER while open. 4xx errors never trip the breaker.

Circuit Breaker Configuration

Default settings added to package.json under cds.agents.circuitBreaker:

{
  "errorThresholdPercentage": 50,
  "volumeThreshold": 10,
  "resetTimeout": 30000,
  "rollingCountTimeout": 10000
}

Import Updates

• lib/agents/middleware/content-filter.js and lib/models/aicore.js now import from ../../utils/resilience.js
• @sap-cloud-sdk/resilience removed from package.json dependencies

Test Improvements

• Replaced brittle deep-require hacks to access @sap-cloud-sdk/resilience internals with a proper OData resetBreakers() action exposed on the test service
• Circuit breaker volumeThreshold lowered to 2 in the test environment for faster test execution
• Test loop counts updated to match the new lower threshold

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PR Bot Information

Version: 1.31.13

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