[EthanPlant]

Summary

Normalize Reddit subreddit configuration values before rendering.

Elsewhere already accepted subreddit names such as r/example, but values written as /r/example were only partially normalized. This produced output like:

r//r/example

This change accepts the following equivalent forms:

example
r/example
/r/example

All three are normalized to:

example

before Elsewhere generates the Reddit preview and structured render artifact.

Changes

• Add a small normalize_subreddit helper.
• Trim surrounding whitespace.
• Remove either an r/ or /r/ prefix.
• Apply normalization consistently to rendered output and artifact metadata.
• Add tests covering each supported input form.

Testing

Added unit tests verifying that:

• example remains example
• r/example becomes example
• /r/example becomes example
• surrounding whitespace is ignored
• each form renders as Subreddit: r/example

Closes #1