docs: fix missing API entries (#3111)

following up on
https://discord.com/channels/859816885297741824/1162726738774720574/1211715924613275681

several things here:
- `docs/api/.*json` were out-of-date — seems like fetch-api-source
should run automatically? shouldn't `build-api` also override this
directory? in particular, tldraw.api.json still had a ton of references
to the old @tldraw/tldraw package
- the main problem was that `generateApiContent` was failing silently.
we were relying on Promises and this broke silently because we never
handled exceptions. i got rid of the Promise as it was unnecessary and
made the exceptions bubble up
- two things were broken in the docs and those are fixed, so now the
missing entries will resurface

### Change Type

- [x] `documentation` — Changes to the documentation only[^2]

---------

Co-authored-by: Steve Ruiz <steveruizok@gmail.com>

packages/tldraw/api/api.json

@@ -15704,7 +15704,7 @@
         {
           "kind": "Variable",
           "canonicalReference": "tldraw!TldrawImage:var",
-          "docComment": "/**\n * A renderered SVG image of a Tldraw snapshot.\n *\n * @example\n * ```tsx\n * <TldrawImage snapshot={snapshot} />\n * \tsnapshot={snapshot}\n * \tpageId={pageId}\n * \tbackground={false}\n *  darkMode={true}\n *  bounds={new Box(0,0,600,400)}\n *  scale={1}\n * />\n * ```\n *\n * @public\n */\n",
+          "docComment": "/**\n * A renderered SVG image of a Tldraw snapshot.\n *\n * @example\n * ```tsx\n * <TldrawImage\n * \tsnapshot={snapshot}\n * \tpageId={pageId}\n * \tbackground={false}\n *  darkMode={true}\n *  bounds={new Box(0,0,600,400)}\n *  scale={1}\n * />\n * ```\n *\n * @public\n */\n",
           "excerptTokens": [
             {
               "kind": "Content",
@@ -19142,7 +19142,7 @@
         {
           "kind": "TypeAlias",
           "canonicalReference": "tldraw!TldrawUiProps:type",
-          "docComment": "/**\n * Props for the {@link @tldraw/tldraw#Tldraw} and {@link TldrawUi} components.\n *\n * @public\n */\n",
+          "docComment": "/**\n * Props for the {@link tldraw#Tldraw} and {@link TldrawUi} components.\n *\n * @public\n */\n",
           "excerptTokens": [
             {
               "kind": "Content",

packages/tldraw/src/lib/TldrawImage.tsx

@@ -51,7 +51,7 @@ export type TldrawImageProps = Expand<
  *
  * @example
  * ```tsx
- * <TldrawImage snapshot={snapshot} />
+ * <TldrawImage
  * 	snapshot={snapshot}
  * 	pageId={pageId}
  * 	background={false}

packages/tldraw/src/lib/ui/TldrawUi.tsx

@@ -54,7 +54,7 @@ export interface TldrawUiBaseProps {
 }
 
 /**
- * Props for the {@link @tldraw/tldraw#Tldraw} and {@link TldrawUi} components.
+ * Props for the {@link tldraw#Tldraw} and {@link TldrawUi} components.
  *
  * @public
  */