* feat(retry): add persistent retry mode for unattended CI/CD environments
When running in CI/CD pipelines or background daemon mode, transient API
capacity errors (429/529) should not terminate long-running tasks after a
fixed number of retries. This adds an environment-aware persistent retry
mode that retries indefinitely for transient errors, with exponential
backoff capped at 5 minutes and heartbeat keepalives every 30 seconds to
prevent CI runner timeouts.
* docs: add persistent retry mode documentation
Add environment variable entries (QWEN_CODE_UNATTENDED_RETRY, QWEN_CODE_BG)
to the settings reference, and a new "Persistent Retry Mode" section to the
headless mode docs covering activation, behavior, and CI/CD usage examples.
* refactor(retry): simplify to single explicit env var QWEN_CODE_UNATTENDED_RETRY
Remove QWEN_CODE_BG and CI=true as activation triggers for persistent retry.
Having multiple env vars with identical behavior adds confusion, and silently
activating infinite retry on CI=true is dangerous — a regular CI test hitting
a 429 would hang forever instead of failing fast.
* fix(retry): address PR review feedback
- Forward caller's abortSignal into retryWithBackoff in both
baseLlmClient.ts and geminiChat.ts so persistent waits remain
cancellable (wenshao)
- Re-apply maxBackoff and capMs after jitter so delays strictly
respect stated caps (Copilot)
- Respect shouldRetryOnError in persistent mode so callers can
force fast-fail even for transient 429/529 errors (Copilot)
- Guard sleepWithHeartbeat against infinite loop when heartbeat
interval is <= 0 via Math.max(1, ...) (Copilot)
- Normalize isEnvTruthy with trim/toLowerCase for robust env
var parsing across CI conventions (Copilot)
* test(retry): add missing UT for shouldRetryOnError override and heartbeat zero-interval guard
* fix(retry): do not cap Retry-After delays at maxBackoff
Server-specified Retry-After values should only be limited by the
absolute cap (capMs/6h), not the exponential backoff cap (maxBackoff/5min).
Jitter is also skipped for Retry-After since the server already specified
the exact wait time.
* refactor(retry): align isUnattendedMode with project env parsing convention
Replace custom isEnvTruthy (trim + toLowerCase) with strict matching
(val === 'true' || val === '1') to match parseBooleanEnvFlag used
elsewhere in the codebase. Prevents inconsistent behavior where
'TRUE' or ' 1 ' would activate persistent retry here but not in
telemetry or other env-driven features.
* test(retry): add Retry-After handling tests for persistent mode
Cover three key behaviors:
- Retry-After is NOT capped at maxBackoff (only at capMs)
- Retry-After IS capped at persistentCapMs absolute limit
- Retry-After delays have no jitter applied
* fix(test): add isUnattendedMode to retry.js mock in baseLlmClient tests
The existing vi.mock for retry.js only exported retryWithBackoff.
After adding isUnattendedMode to the retry module, baseLlmClient.ts
imports it, causing all 10 generateJson tests to fail with
'No "isUnattendedMode" export is defined on the mock'.
* fix(retry): wire persistent retry mode into client.ts generateContent
Forward persistentMode and abortSignal to retryWithBackoff() in
GeminiClient.generateContent(), matching the existing wiring in
baseLlmClient.ts and geminiChat.ts.
