Add weeknotes system with first entry

- Add weeknotes landing page with auto-listing of all entries
- Create first weeknote: December 20–27, 2025
- Add Weeknotes to secondary menu alongside Now/Then/Future
- Create custom layout to display all weeknotes chronologically
- Update weeknotes command to use date ranges and current time
- Credit Genehack for weeknotes inspiration

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

content/weeknotes.md

@@ -1,11 +1,10 @@
 ---
 title: Weeknotes
+type: weeknotes
 aliases:
   - /weeknotes/
 ---
 
 Weeknotes are short, personal reflections on the week—what I shipped, read, played, cooked, noticed, and thought about. They're a way to mark time and notice patterns.
 
-The format comes from the [weeknotes movement](https://indieweb.org/weeknotes), which grew out of the UK digital government community and spread through personal blogs. [Giles Turnbull's guide](https://doingweeknotes.com/) and [Tracy Durnell's reflections](https://tracydurnell.com/2024/07/30/using-personal-weeknotes-as-a-tool-for-attention/) shaped my approach.
-
-Browse all weeknotes: [/tags/weeknotes](/tags/weeknotes/)
+The format comes from the [weeknotes movement](https://indieweb.org/weeknotes), which grew out of the UK digital government community and spread through personal blogs. [Giles Turnbull's guide](https://doingweeknotes.com/) and [Tracy Durnell's reflections](https://tracydurnell.com/2024/07/30/using-personal-weeknotes-as-a-tool-for-attention/) shaped my approach. My friend [Genehack](https://genehack.blog/archives/) introduced me to weeknotes and inspired me to start my own after he'd been doing them for well over a year.