[FEATURE] Run custom code after creating session

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://www.apache.org/foundation/policies/conduct)

### Search before asking

- [X] I have searched in the [issues](https://github.com/apache/incubator-kyuubi/issues?q=is%3Aissue) and found no similar issues.

### Describe the feature

Provide a way to startup spark session with custom code. For example add a bunch of `create temp view` so that the user can access them in its sql session.

### Motivation

I need to create temporary views and give access to users

### Describe the solution

Provide an pluggeable interface to run arbiratray code with a spark session

### Additional context

_No response_

### Are you willing to submit PR?

- [ ] Yes. I can submit a PR independently to improve.
- [X] Yes. I would be willing to submit a PR with guidance from the Kyuubi community to improve.
- [ ] No. I cannot submit a PR at this time.

The issue names no files, tests, or entry points. Start by tracing how a Spark session is created and where session-startup extension points could fit; compare the requested temporary-view setup with existing mechanisms. Done means a defined pluggable way to run arbitrary code after session creation, covering the stated temporary-view use case.

Written by the indexing model from the issue text.