fix(runtime): honor isRetryable flag in provider retry classifier

[0xMudit]

Summary

Fixes #3756

The AI SDK wraps TLS/transport failures as \APICallError\ with \isRetryable: true\ and a message like \Cannot connect to API: . Maka's \providerRetryMetadata\ did not check this flag or walk the \cause\ chain, so these failures were classified as non-retryable and the turn exited immediately.

Changes

• **\provider-error-classification.ts**: Added \isRetryableInChain()\ helper that walks up to 8 levels of the error's \cause\ chain looking for \isRetryable: true. Called as a fallback when the classifier doesn't surface a retryable class, or when
  ormalizeProviderError\ returns undefined.
• **\provider-error-classification.test.ts**: Added two regression tests:
  1. TLS failure with the exact message from the issue report (\decryption failed or bad record mac) — verifies it's now retryable.
  2. Wrapped cause error with \isRetryable: true\ when the top-level error has no structured evidence — verifies the cause flag is honored.

Verification

• 
  pm --workspace @maka/runtime run build: passes
• 
  pm --workspace @maka/runtime test: 17/17 pass (including 2 new regression tests)
• 
  pm --workspace @maka/core test: 656/656 pass
• 
  pm run lint: passes
• 
  pm run format:check: passes

AI use

• Generative tooling made a substantive contribution

Tool(s) and scope: opencode/big-pickle — diagnosed root cause, implemented fix and regression tests

Checklist

• Tests cover the change and fail without it
• Lint, format, typecheck and the affected suites pass locally

Does this PR entail a change in behavior?

• Yes — transport failures marked retryable by the AI SDK are now retried instead of terminating the turn

[Astro-Han]

Update on b61f988a42:

[P2] isRetryableInChain ignores outer isRetryable:false, causes false retry

APICallError(400,false,cause=APICallError(true)) is judged retryable, sending a hard 4xx into up to 10 provider retries. Fix: give nearest explicit boolean (especially false) authority and add regression test.

Also P3: RetryError.lastError unwrapping inconsistency between classifier and helper — unify boundary.

简体中文

重试判断越过显式不可重试标记。