Enable users to submit code snippets

Implement a form to allow users to submit code snippets along with relevant metadata, such as title, description, tags, and programming language. Validate user inputs and store submitted snippets in the database.

## Expectations

- Users can submit a code snippet with a title, description, tags, and programming language.
- Submitted code snippets are saved in the database.

Start in the snippit-ui React/TypeScript frontend and trace how it communicates with the Rails/Postgres backend. Locate the relevant form and persistence entry points, then verify validation for title, description, tags, and programming language. Done means users can submit a validated snippet and the submitted record is saved in the database.

Written by the indexing model from the issue text.