feat: add retry utility with exponential backoff

[dsm20]

Adds a retry utility with exponential backoff and jitter for testing comprehension gate inline results.

[github-actions]

Comprehension Gate

Answer the questions below in order to merge.

Q1. Under what condition will the withRetry function rethrow the lastError wrapped in a RetryError immediately after the first failed attempt, without any further retries?

• A) If maxRetries is set to 0 and the shouldRetry function returns true for the initial error.
• B) If maxRetries is set to 1 and the shouldRetry function returns false for the initial error.
• C) If maxRetries is set to 0 and the shouldRetry function returns false for the initial error.
• D) If maxRetries is set to 1 and the shouldRetry function is not provided, implying default true.

Q2. Consider the exponential backoff with jitter implemented in withRetry. If baseDelayMs is 1000, what is the minimum possible delay before the third retry attempt (i.e., after the second failure)?

• A) 1500 ms
• B) 3000 ms
• C) 2250 ms
• D) 5000 ms

Q3. What is the primary purpose of the isRetryable function provided in src/retry.mjs?

• A) To be used as a default onRetry callback to log specific error types.
• B) To determine if an error should trigger a retry attempt when passed to the shouldRetry option of withRetry.
• C) To categorize errors for reporting purposes, indicating whether they are transient or permanent.
• D) To explicitly prevent retries for client-side errors (e.g., 4xx HTTP status codes).

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Reply in a format like this:

1. A
2. C
3. B

Questions are based on commit a4a6e94. Pushing new commits regenerates the questions.

Result — PASSED

Score: 3/3 | Q1: PASS | Q2: PASS | Q3: PASS

Comprehension gate passed — this PR is cleared to merge.

[dsm20]

1. C
2. B
3. B