reopening from nov-mode resets root NOTER_PAGE instead of restoring saved location #121

Description

When org-noter is started from an EPUB document buffer (nov-mode) with org- noter-auto-save-last-location enabled, reopening the session from the document
side does not restore the saved location.

If the root note has a location like:

:NOTER_PAGE: (12 . 622)

reopening org-noter from the EPUB buffer jumps near the beginning, and the property
is rewritten to something like:

:NOTER_PAGE: (0 . 131)

This looks like the document-side startup path is not correctly handling NOV-style
location values.

Btw, I looked into the code and found that the key problem may be in org-noter.el, where the saved root location is read using string-to-number and (12 . 622) becomes 0.

Steps to Reproduce

1. Open an EPUB in nov-mode
2. Run M-x org-noter
3. Read forward until the root heading has a saved location such as:
   :NOTER_PAGE: (12 . 622)
4. Kill the session
5. Reopen the EPUB and run M-x org-noter again

Backtrace

No backtrace. This seems to be a logic bug rather than a thrown error.

Expected Results

org-noter should reopen at the saved EPUB location, and the existing NOTER_PAGE
should remain valid.

Actual Results

org-noter reopens near the beginning, and the root NOTER_PAGE is overwritten, e.g.
from (12 . 622) to (0 . 131).

Environment

• Emacs: 30.2
• Org: 9.8-pre
• org-noter: 20260108.2346
• nov: 20251213.1501
• macOS