fix(reliability): use wall-clock time in circuit breaker for cross-pod consistency

[NP-compete]

Closes #232

Summary

• Replace time.monotonic() with time.time() in CircuitBreaker.is_open and CircuitBreaker.record_failure() so timestamps stored in Redis remain valid across pod restarts
• Add test_half_open_after_pod_restart test that simulates a pod restart by writing a past wall-clock timestamp to the Redis mock and verifying a new breaker instance transitions to half-open

Test plan

• New test: test_half_open_after_pod_restart verifies circuit recovers when reading old timestamps from Redis
• All 44 existing error handling tests pass (including time-sensitive half-open tests)
• Pre-commit hooks pass (ruff, mypy, bandit)

[coderabbitai]

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• tests/unit/test_error_handling.py

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Walkthrough

The circuit breaker now uses time.time() for failure timestamps and reset-timeout checks. A Redis-backed test verifies that a new instance enters the half-open state after the persisted failure timestamp expires across a pod restart.

Suggested reviewers: anish701

Merge Risk: ⚪ Minimal · up to a71b3

The PR updates circuit-breaker timestamp handling for cross-pod recovery and adds focused coverage; no actionable merge-blocking risk remains.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the circuit-breaker timing fix and its cross-pod consistency purpose.
Description check	✅ Passed	The description directly explains the wall-clock timestamp fix, regression test, and validation results.
Linked Issues check	✅ Passed	The changes satisfy issue #232 by using wall-clock timestamps and testing recovery after a pod restart.
Out of Scope Changes check	✅ Passed	The code and test changes remain within the linked issue's circuit-breaker timestamp and pod-restart recovery scope.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

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• Create PR with unit tests

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[coderabbitai]

Actionable comments posted: 1

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Inline comments:
In `@tests/unit/test_error_handling.py`:
- Around line 418-419: Add an assertion in the test before overwriting
last_failure_ts to verify the persisted timestamp from the preceding
record_failure call is present and uses the expected wall-clock timestamp
behavior. Keep the existing past-timestamp setup and subsequent test flow
unchanged.

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Fix all unresolved CodeRabbit comments on this PR:

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• deep_agent/src/error_handling.py
• tests/unit/test_error_handling.py

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• redhat-data-and-ai/template-ui (manual)

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[vishnusrichand]

LGTM

[coderabbitai]

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