Fix double border on custom feed posts (web)

Add missing visibility check for ageAssuranceBanner on non-discover
feeds. The banner was being added to the feedItems array without
checking ageAssuranceBannerState.visible, causing the first post's
rowIndex to be 1 instead of 0, which prevented hideTopBorder from
being set correctly. This was particularly visible on web when
directly navigating to a custom feed URL.

src/analytics/misc/refParams.js

@@ -0,0 +1,16 @@
+/**
+ * This is used for our own Bluesky post embeds, and maybe other things.
+ *
+ * In the case of our embeds, `ref_src=embed`. Not sure if `ref_url` is used.
+ */
+var _a, _b;
+import * as env from '#/env';
+var refSrc = '';
+var refUrl = '';
+if (env.IS_WEB) {
+    var params = new URLSearchParams(window.location.search);
+    refSrc = (_a = params.get('ref_src')) !== null && _a !== void 0 ? _a : '';
+    refUrl = decodeURIComponent((_b = params.get('ref_url')) !== null && _b !== void 0 ? _b : '');
+}
+export var src = refSrc;
+export var url = refUrl;