fix: Resolve Google Calendar password prompts every 10 minutes

Problem: oauth2-auto.plist passphrase requested every ~10 minutes during
gcal-sync auto-sync, interrupting workflow despite 400-day gpg-agent cache.

Root cause: auth-config.el was setting GPG_AGENT_INFO to nil, telling
Emacs to ignore gpg-agent entirely. Additionally, plstore caching was
loading too late in org-gcal-config.

Solution:
- Disabled GPG_AGENT_INFO override to allow gpg-agent usage
- Added auth-source-cache-expiry (24-hour cache for credentials)
- Moved plstore configuration from org-gcal-config to auth-config
- Enabled plstore-cache-passphrase-for-symmetric-encryption globally
- Set plstore-encrypt-to nil for symmetric encryption

Files modified:
- modules/auth-config.el: Added plstore config, removed agent bypass
- modules/org-gcal-config.el: Removed duplicate plstore config
- docs/NOTES.org: Session notes documenting fix

Testing: Restart Emacs and verify no password prompts for 30+ minutes.

0 files changed, 0 insertions, 0 deletions