Merge commit from fork

* SP-2025-03.1 always wrap icon&thumbnail URLs

if they're not HTTP URLs, the frontend won't be able to display them
anyway (`<img src="mailto:…">` or '<div stile="background-image:
url(nntp:…)">` aren't going to work!), so let's always run them through the
media proxy, which will fail harder (fetching a `javascript:` URL
won't do anything in the backend, might do something in the frontend)
and will always protect the client's address in cases like `gemini:`
where the browser could try to fetch

* SP-2025-03.2 use object binding for more styles

interpolating a random (remote-controlled!) string into a `style`
attribute is a bad idea; using VueJS object binding, we should get
proper quoting and therefore safe parse failures instead of CSS
injections / XSS

* SP-2025-03.3 slightly more robust "self" URL handling

parse URLs instead of treating them as strings; this is still not
perfect, but the `URL` class only handles full URLs, not relative
ones, so there's so way to ask it "give me a URL object that
represents this resource relative to this base URL"

notice that passing very weird URLs to `MkUrl` and `MkUrlPreview` will
break the frontend (in dev mode) because there's an untrapped `new
URL(…)` that may explode; production builds seem to safely ignore the
error, though

---------

Co-authored-by: dakkar <dakkar@thenautilus.net>

packages/backend/src/server/web/UrlPreviewService.ts

@@ -37,12 +37,10 @@ export class UrlPreviewService {
 	@bindThis
 	private wrap(url?: string | null): string | null {
 		return url != null
-			? url.match(/^https?:\/\//)
-				? `${this.config.mediaProxy}/preview.webp?${query({
-					url,
-					preview: '1',
-				})}`
-				: url
+			? `${this.config.mediaProxy}/preview.webp?${query({
+				url,
+				preview: '1',
+			})}`
 			: null;
 	}