[Enhancement] Make Peek Messages API available for non-admin clients

### Search before asking

- [x] I searched in the [issues](https://github.com/apache/pulsar/issues) and found nothing similar.

### Motivation

The current Peek Messages API is under the Admin API with `consume` permissions. We needed the ability for non-admin applications to peek the topic partitions.

### Solution

We propose adding a new endpoint to the Lookup API that leverages the internal implementation of the existing Peek Messages API. This enhancement will expose the Peek Messages functionality via the Lookup API, providing clients with an alternative access method. The internal logic of the Peek Messages API remains unchanged having minimal impact on existing functionalities.

### Alternatives

_No response_

### Anything else?

_No response_

### Are you willing to submit a PR?

- [x] I'm willing to submit a PR!

Start by locating the existing Peek Messages API and the Lookup API entry points, then trace how the internal peek implementation handles topic partitions and permissions. Done means exposing the existing Peek Messages functionality through Lookup for non-admin clients while leaving the current Admin API behavior unchanged.

Written by the indexing model from the issue text.