✨ feat: enhance medialib image handling and add asset URL resolution

- Implemented `resolveApiAssetUrl` function to normalize asset URLs based on API base.
- Updated `MedialibImage` component to utilize new asset URL resolution and added support for alt text and class properties.
- Enhanced image loading behavior with improved width measurement and focal point handling.
- Added placeholder image handling and improved accessibility with alt text.
- Introduced new test script for auditing broken links in skill documentation.
- Expanded seeded test content to include medialib entries and updated related tests for pagebuilder previews.
- Improved global setup and teardown logging for clarity on seeded content management.

frontend/src/lib/utils.ts

@@ -1,3 +1,32 @@
+import { get } from "svelte/store"
+import { apiBaseURL } from "../config"
+import { apiBaseOverride } from "./store"
+
+function isAbsoluteUrl(url: string | undefined): boolean {
+    return !!url && (/^(?:https?:)?\/\//.test(url) || url.startsWith("data:") || url.startsWith("blob:"))
+}
+
+function normalizeBase(base: string | null | undefined): string | null {
+    return base ? base.replace(/\/+$/, "") + "/" : null
+}
+
+export function resolveApiAssetUrl(
+    url: string | null | undefined,
+    apiBase: string | null | undefined = get(apiBaseOverride) || apiBaseURL
+): string | null | undefined {
+    if (!url || isAbsoluteUrl(url) || !url.startsWith("/assets/")) {
+        return url
+    }
+
+    const normalizedApiBase = normalizeBase(apiBase)
+
+    if (!normalizedApiBase) {
+        return url
+    }
+
+    return normalizedApiBase + "_/assets/" + url.replace(/^\/+/, "")
+}
+
 export function debounce<T extends (...args: never[]) => void>(
     func: T,
     wait: number