include quoted posts with music links

turbostream hydrates quoted post content, so we can now detect
music links in posts that quote other music posts.

checks:
- embed.record.value.embed.external.uri (quoted post link cards)
- embed.record.value.facets (quoted post inline links)
- embed.record.record.value... (recordWithMedia variant)

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

Co-Authored-By: Claude Opus 4.5 <[e-mail]>

src/feed/filter.zig

···
         if (containsMusicDomain(uri)) return true;
     }
 
+    // check quoted post's embed (embed.record.value.embed.external.uri)
+    if (zat.json.getString(val, "embed.record.value.embed.external.uri")) |uri| {
+        if (containsMusicDomain(uri)) return true;
+    }
+
+    // check recordWithMedia quoted post (embed.record.record.value.embed.external.uri)
+    if (zat.json.getString(val, "embed.record.record.value.embed.external.uri")) |uri| {
+        if (containsMusicDomain(uri)) return true;
+    }
+
     // check facets (inline links)
-    const facets = zat.json.getArray(val, "facets") orelse return null;
+    if (zat.json.getArray(val, "facets")) |facets| {
+        if (checkFacetsForMusic(facets)) return true;
+    }
+
+    // check quoted post's facets
+    if (zat.json.getArray(val, "embed.record.value.facets")) |facets| {
+        if (checkFacetsForMusic(facets)) return true;
+    }
+
+    return null;
+}
+
+fn checkFacetsForMusic(facets: []const json.Value) bool {
     for (facets) |facet| {
         const features = zat.json.getArray(facet, "features") orelse continue;
         for (features) |feature| {
···
             if (containsMusicDomain(uri)) return true;
         }
     }
-
-    return null;
+    return false;
 }
 
 fn containsMusicDomain(uri: []const u8) bool {
···
         if (detectPlatform(uri)) |p| result.add(p);
     }
 
+    // check quoted post's embed
+    if (zat.json.getString(val, "embed.record.value.embed.external.uri")) |uri| {
+        if (detectPlatform(uri)) |p| result.add(p);
+    }
+
+    // check recordWithMedia quoted post
+    if (zat.json.getString(val, "embed.record.record.value.embed.external.uri")) |uri| {
+        if (detectPlatform(uri)) |p| result.add(p);
+    }
+
     // check facets
-    const facets = zat.json.getArray(val, "facets") orelse return result;
+    if (zat.json.getArray(val, "facets")) |facets| {
+        detectPlatformsInFacets(facets, &result);
+    }
+
+    // check quoted post's facets
+    if (zat.json.getArray(val, "embed.record.value.facets")) |facets| {
+        detectPlatformsInFacets(facets, &result);
+    }
+
+    return result;
+}
+
+fn detectPlatformsInFacets(facets: []const json.Value, result: *PlatformSet) void {
     for (facets) |facet| {
         const features = zat.json.getArray(facet, "features") orelse continue;
         for (features) |feature| {
···
             if (detectPlatform(uri)) |p| result.add(p);
         }
     }
-
-    return result;
 }
 
 // -----------------------------------------------------------------------------