feat(api): retry configuration for api block (#3329)

* fix(api): add configurable request retries

The API block docs described automatic retries, but the block didn't expose any retry controls and requests were executed only once.

This adds tool-level retry support with exponential backoff (including Retry-After support) for timeouts, 429s, and 5xx responses, exposes retry settings in the API block and http_request tool, and updates the docs to match.

Fixes #3225

* remove unnecessary helpers, cleanup

* update desc

* ack comments

* ack comment

* ack

* handle timeouts

---------

Co-authored-by: Jay Prajapati <79649559+jayy-77@users.noreply.github.com>

apps/docs/content/docs/en/blocks/api.mdx

@@ -95,11 +95,17 @@ const apiUrl = `https://api.example.com/users/${userId}/profile`;
 
 ### Request Retries
 
-The API block automatically handles:
-- Network timeouts with exponential backoff
-- Rate limit responses (429 status codes)
-- Server errors (5xx status codes) with retry logic
-- Connection failures with reconnection attempts
+The API block supports **configurable retries** (see the block’s **Advanced** settings):
+
+- **Retries**: Number of retry attempts (additional tries after the first request)
+- **Retry delay (ms)**: Initial delay before retrying (uses exponential backoff)
+- **Max retry delay (ms)**: Maximum delay between retries
+- **Retry non-idempotent methods**: Allow retries for **POST/PATCH** (may create duplicate requests)
+
+Retries are attempted for:
+
+- Network/connection failures and timeouts (with exponential backoff)
+- Rate limits (**429**) and server errors (**5xx**)
 
 ### Response Validation