Fix Fountain.fm episode cards: use Tauri HTTP plugin for CORS bypass

- Import fetch from @tauri-apps/plugin-http (browser fetch was CORS-blocked)
- Add fountain.fm to Tauri HTTP capability scope
- Extract og:audio meta tag for reliable audio URL resolution
- Parse OG title into show name + episode title

src-tauri/Cargo.lock

@@ -5318,7 +5318,7 @@ checksum = "accd4ea62f7bb7a82fe23066fb0957d48ef677f6eeb8215f372f52e48bb32426"
 
 [[package]]
 name = "vega"
-version = "0.10.1"
+version = "0.11.0"
 dependencies = [
  "futures-util",
  "hex",

src-tauri/capabilities/default.json

@@ -14,7 +14,8 @@
         { "url": "https://nostr.build/**" },
         { "url": "https://void.cat/**" },
         { "url": "https://nostrimg.com/**" },
-        { "url": "https://relay.vertexlab.io/**" }
+        { "url": "https://relay.vertexlab.io/**" },
+        { "url": "https://fountain.fm/**" }
       ]
     },
     "dialog:default",