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### What

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obvious)? -->

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This PR introduces pre-route plugins. A pre-route plugin sits at the
router level. It will catch all the OTHER routes (other than existing
routes like `/graphql`, `/v1/explain`, etc.) and, based on the
configuration, call some external webhook to handle the request.

Currently, we can configure the following:

- The regex for the URL to match on
- The request to the webhook:
  - headers
  - method
  - raw query

The feature is currently hidden behind a flag.

In case of multiple pre-route plugins, the first matching pre-route
plugin will handle the request.

Currently, the pre-route plugin can handle only GET requests to the
engine, but we can easily expand this to handle other requests.

A sample request being handled by the preroute plugin:

![image](https://github.com/user-attachments/assets/1c7d96bd-72cd-41ae-abe7-b703cbac41ae)

### How

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steps)? -->

We have made the following changes:
- Make our tracing library more lenient for trace span names.
- Implement the middleware.

V3_GIT_ORIGIN_REV_ID: cc9913c7071a65c2da545f11909f72fccd798862