Feature Request: Allow custom template for note export

This is a big ask, but submitting just in case this would be valuable to other users.

The Issue

Currently, there is no way to customize the way markdown notes are generated for each note in Google Keep.

Proposed Solution

Using a templating engine like Jinja, users could be able to specify their own Jinja template to use for generating markdown notes.

For example:

Below is the default export format:

- I'd like to find system for (X)
- Is a hot dog a sandwich?
- Add questions to document

Created: 2024-01-15 05:40:34   ---   Updated: 2024-01-15 05:40:34

[https://keep.google.com/#NOTE/1705297229969.1234682776](https://keep.google.com/#NOTE/1705297229969.1234682776)

Using a custom template, the user could have their markdown notes formatted in the following way if they prefer having the note metadata stored in markdown frontmatter:

---
created: 2024-01-15T05:40:34
updated:  2024-01-15T05:40:34
note-url: [https://keep.google.com/#NOTE/1705297229969.1234682776](https://keep.google.com/#NOTE/1705297229969.1234682776)
---
- I'd like to find system for (X)
- Is a hot dog a sandwich?
- Add questions to document

The template file for the above would look something like:

---
created: {{ created_at }}
updated: {{ updated_at }}
note-url: [{{ note_url }}]({{ note_url }})
---
{{ note_content }}

The issue does not name any files, tests, or entry points. Begin by locating the note export code and its existing markdown formatting path, then determine how a user-supplied template would be configured and validated. Done means custom templates can render note content and metadata while the current default export remains available.