[Flow.Launcher.Plugin.BrowserBookmark] Feature Request: Advanced Exclusion Rules (List-based filtering for Folders/Keywords)

**Is your feature request related to a problem? Please describe.**

Yes. I am using the Flow.Launcher.Plugin.BrowserBookmark plugin, and currently, it indexes all bookmarks from the browser without exception. I have specific needs to filter out content from Flow Launcher's search results, such as:

1. Hiding specific private folders (e.g., "Private" or "Work").
2. Filtering out bookmarks that contain certain keywords (e.g., "NSFW" or "Backup"). A simple valid/invalid toggle is not enough.

**Describe the solution you'd like**

I would like to see an Advanced Filter Rules section added to the BrowserBookmark plugin settings. Instead of a simple text box, please implement a list-based UI where users can add multiple distinct exclusion rules.

Proposed UI & Logic: The settings interface should allow users to "Add Rule" with the following fields:

1. Rule Type: A dropdown to select the target of the filter.

- Folder Name (Exact Match): The plugin should skip indexing any folder (and its children) that matches this name exactly.
- Keyword (Contains): The plugin should skip any bookmark whose title or URL contains this keyword.

2. Value: A text input for the specific folder name or keyword string.

3. Active Status: A checkbox/toggle to enable or disable specific rules without deleting them.

Example Scenario:
- Rule 1: Type=Folder Name, Value=MySecretDocs -> Action: Recursively skip this folder.
- Rule 2: Type=Keyword, Value=token= -> Action: Skip any URL containing authentication tokens.

**Describe alternatives you've considered**

I considered modifying ChromiumBookmarkLoader.cs locally to hardcode these exclusions, but this is not sustainable for updates. A structured, UI-based rule list is the best solution for user experience.

**Additional context**

This feature would specificially improve the BrowserBookmark plugin by giving users granular control over their search scope.

Start with ChromiumBookmarkLoader.cs and locate the BrowserBookmark plugin's settings entry point. Trace how bookmarks and folders are indexed, then determine how the requested folder and keyword rules, including active status, should affect indexing. Done means users can add, edit, disable, and apply multiple exclusion rules as described.

Written by the indexing model from the issue text.