fix: exclude research-spotlight dir from generic content collection (closes #113)

The 80 spotlight MDX files under content/content/reactome-research-spotlight
also matched the parent 'content' collection (path content/content),
yielding ~2880 "file in multiple collections" warnings every startup and
two conflicting edit schemas in the TinaCMS sidebar: one with
description/image (Content) and one with date/author/tags (Spotlights).
The frontmatter on disk uses date/tags, so the Spotlights collection is
the correct owner.

Add a match.exclude pattern (mirroring the existing news/** exclude on
the 'about' collection) so spotlight files belong to Spotlights only.
The Content sidebar entry now lists just the three real /content/*.mdx
pages (covid-19, index, orcid); spotlights remain editable under the
"Reactome Research Spotlights" sidebar entry. No routing or on-disk
changes; this is purely a CMS-side disambiguation.

Verified post-restart: warning count drops from ~2880 to 0, both
collections still in the generated schema, beta + admin both return 200.

Author: adamjohnwright

projects/website-angular/tina/config.ts

@@ -58,6 +58,9 @@ export default defineConfig({
         label: "Content",
         path: "content/content",
         format: "mdx",
+        match: {
+          exclude: "reactome-research-spotlight/**",
+        },
         fields: [
           { type: "string", name: "title", label: "Title", isTitle: true, required: true },
           { type: 'string', name: "description", label: "Description" },