Support custom scripts/hooks

Describe the feature you'd like

Support hooking custom user code into the bookmark process. A /scripts directory could be mounted where named callbacks would be exported. For example, my-script.js would expose:

// --- Pseudocode for illustration purposes ---
module.exports = {
  async onBookmark(input, bookmark) {
    if (input.url && input.url.host.contains('youtube.com')) {
      bookmark.tags.add('videos');
    }
    if (input.url && input.url.host.contains('reddit.com')) {
      if (input.url.path.startswith('/r/funny') {
        bookmark.tags.add('entertainment')
      } else if (input.url.path.startswith('/r/programming') {
        bookmark.tags.add('technology')
        bookmark.tags.add('learning')
      }
    }
    return bookmark
  }
}

Similarly, we could have a onAITags to clean up the AI generated tags, onAiPrompt to fine tune a prompt, onContentCaptured, onSummary, and so on.

Describe the benefits this would bring to existing Hoarder users

There are some key sites where I commonly save links and I would like to apply some pre/postprocessing. Automatic tagging would be beneficial in a site such as reddit where it depends on which subreddit the bookmark was captured. This would also make it possible for third party integrations such as caling a webhook when something of interest has happened.

Another use case that comes to mind is parsing domain-specific languages for text notes.

Can the goal of this request already be achieved via other means?

No, the closest thing is customizing the AI prompts.

Have you searched for an existing open/closed issue?

[X] I have searched for existing issues and none cover my fundamental request

Additional context

No response

hoarder-app / hoarder