Radio starts empty and fills from the Store (Add to Radio, including The Journey FM); iCloud connect falls back to the calendar home beside the principal

- Store > Radio is the station finder with Add to Radio / Added; Radio under Listen lists only what was added
- Fix the Radio tab going blank (the router passed its arguments as the Store host)
- iCloud: when the account reports no calendar home, try /<id>/calendars/, and say what iCloud answered if that fails

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

README.md

@@ -153,7 +153,7 @@ playing an episode or pressing the button still works. Settings -> Health shows
 
 ## Store
 
-One **Store** tab (turn it on per person) with sections for **Books** (the free book sources, Open Library and any OPDS catalogue), **Audiobooks** (LibriVox) and **Radio** (the station finder), each shown only to people who have that tab, plus **My Store**. The old Book store and Free audiobooks buttons now open the Store.
+One **Store** tab (turn it on per person) with sections for **Books** (the free book sources, Open Library and any OPDS catalogue), **Audiobooks** (LibriVox) and **Radio** (the station finder), each shown only to people who have that tab, plus **My Store**. The old Book store and Free audiobooks buttons now open the Store. **Radio** under Listen starts empty: find stations in the Store's Radio section (The Journey FM is listed there too) and tap *Add to Radio*; only what you add appears under Listen, and you can remove it again. Someone without the Store tab keeps the station finder in Radio itself.
 
 **My Store** is your own catalogue, for everyone who has the Store tab. The admin adds items with **Add**: upload files, or copy a file from their Seafile (**From Files**), with an optional cover picture.
 - **Books** (EPUB, PDF, MOBI, AZW3, DOCX): *Add to my library* puts a copy on that person's shelf, or download it.