Emdash source with visual editor image upload fix

Fixes:
1. media.ts: wrap placeholder generation in try-catch
2. toolbar.ts: check r.ok, display error message in popover

packages/contentful-to-portable-text/src/blocks/code-block.ts

@@ -0,0 +1,12 @@
+import type { ArbitraryTypedObject } from "@portabletext/types";
+
+import type { ContentfulEntry } from "../types.js";
+
+export function transformCodeBlock(entry: ContentfulEntry, key: string): ArbitraryTypedObject {
+	return {
+		_type: "code",
+		_key: key,
+		code: (entry.fields.code as string) ?? "",
+		language: (entry.fields.language as string) ?? "",
+	};
+}

packages/contentful-to-portable-text/src/blocks/embedded-html.ts

@@ -0,0 +1,12 @@
+import type { ArbitraryTypedObject } from "@portabletext/types";
+
+import type { ContentfulEntry } from "../types.js";
+
+/** HTML is preserved verbatim — sanitization is the renderer's responsibility. */
+export function transformEmbeddedHtml(entry: ContentfulEntry, key: string): ArbitraryTypedObject {
+	return {
+		_type: "htmlBlock",
+		_key: key,
+		html: (entry.fields.customHtml as string) ?? "",
+	};
+}

packages/contentful-to-portable-text/src/blocks/image-block.ts

@@ -0,0 +1,29 @@
+import type { ArbitraryTypedObject } from "@portabletext/types";
+
+import { sanitizeUri } from "../sanitize.js";
+import type { ContentfulEntry, ContentfulIncludes } from "../types.js";
+
+export function transformImageBlock(
+	entry: ContentfulEntry,
+	includes: ContentfulIncludes,
+	key: string,
+): ArbitraryTypedObject {
+	const assetLink = entry.fields.assetFile as { sys?: { id?: string } } | undefined;
+	const assetId = assetLink?.sys?.id;
+	const asset = assetId ? includes.assets.get(assetId) : undefined;
+
+	const src = asset?.url ? (asset.url.startsWith("//") ? `https:${asset.url}` : asset.url) : "";
+
+	return {
+		_type: "image",
+		_key: key,
+		asset: {
+			src,
+			alt: asset?.description ?? asset?.title ?? "",
+			width: asset?.width,
+			height: asset?.height,
+		},
+		linkUrl: entry.fields.linkUrl ? sanitizeUri(entry.fields.linkUrl as string) : undefined,
+		size: (entry.fields.size as string) ?? undefined,
+	};
+}