Add a browser-facing Miniflux URL and link feeds to their entries page

The pipeline talks to Miniflux on loopback, so links meant for a person
need their own base. `[miniflux].public_url` defaults to base_url, and
`feed_url` builds the web UI's `/feed/{id}/entries` page, which the feeds
dashboard now uses instead of the non-existent `/feeds/{id}` route.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YWmCpUojfHXhSZ2129Z7Nv

config.example.toml

@@ -30,6 +30,8 @@ interests_opml = "data/scour-interests.opml"
 
 [miniflux]
 base_url = "http://127.0.0.1:8082"
+# Browser-facing Miniflux web UI URL; defaults to base_url.
+# public_url = "https://miniflux.example.com"
 # api_key via DAILY_EPUB_MINIFLUX__API_KEY env
 page_limit = 250