fix(client): include acquire timeout duration in pool timeout error message

[Piyush0049]

Description

This pull request addresses a maintainer TODO comment (// TODO: message) in pool.ts by formatting the TimeoutError message thrown when acquireTimeout expires while waiting for a client from the pool.

Background

Previously, when a task timed out waiting for an available client in RedisClientPool, the operation rejected with a static string TimeoutError('Timeout waiting for a client'). This lacked diagnostic details about the configured timeout duration.

Key Changes

1. Formatted Error Message: Updated pool.ts to dynamically include the configured timeout duration in milliseconds: Timeout waiting for a client after ${acquireTimeout}ms.
2. Added Unit Test: Added a test case in pool.spec.ts (rejects with TimeoutError when acquireTimeout expires) to verify that acquire timeout rejections produce a TimeoutError with the formatted message.

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Checklist

• Does npm test pass with this change (including linting)?
• Is the new or changed code fully tested?
• Is a documentation update included (if this change modifies existing APIs, or introduces new ones)?

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Note

Low Risk
Only the timeout error message text changes; pool acquire logic is unchanged aside from clearer diagnostics.

Overview
When RedisClientPool cannot hand out a client before acquireTimeout, the rejection now uses a TimeoutError message that includes the configured wait time (e.g. Timeout waiting for a client after 50ms) instead of a fixed string.

A pool integration test was added to hold the sole client busy, trigger a second execute with a short acquireTimeout, and assert the error type and message.

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