docs: remove OpenMemory references from docs, README, and issue templates (#4520)

docs/introduction.mdx

@@ -31,7 +31,7 @@ mode: "custom"
     </h2>
   </div>
 
-  <div className="grid gap-6 sm:grid-cols-2 lg:grid-cols-3">
+  <div className="grid gap-6 sm:grid-cols-2">
     <a
       href="/platform/overview"
       className="group flex h-full flex-col overflow-hidden rounded-2xl border border-gray-200 dark:border-zinc-800/40 bg-white dark:bg-zinc-900/40 transition hover:border-primary/60 hover:bg-gray-50 dark:hover:bg-zinc-900"
@@ -84,31 +84,6 @@ mode: "custom"
       </div>
     </a>
 
-    <a
-      href="/openmemory/overview"
-      className="group flex h-full flex-col overflow-hidden rounded-2xl border border-gray-200 dark:border-zinc-800/40 bg-white dark:bg-zinc-900/40 transition hover:border-primary/60 hover:bg-gray-50 dark:hover:bg-zinc-900"
-    >
-      <img
-        className="block dark:hidden aspect-[4/3] w-full object-cover"
-        src="/images/docs thumbnails/light/mem0_openmemory.png"
-        alt="OpenMemory thumbnail"
-        style={{pointerEvents: "none"}}
-      />
-      <img
-        className="hidden dark:block aspect-[4/3] w-full object-cover"
-        src="/images/docs thumbnails/dark/mem0_openmemory.png"
-        alt="OpenMemory thumbnail"
-        style={{pointerEvents: "none"}}
-      />
-      <div className="flex flex-1 flex-col gap-3 px-5 pb-6 pt-5 text-left">
-        <h3 className="text-base font-semibold text-gray-900 dark:text-zinc-100 group-hover:text-primary">
-          OpenMemory
-        </h3>
-        <p className="text-sm text-gray-600 dark:text-zinc-400">
-          Workspace-based memory for teams collaborating across agents and projects.
-        </p>
-      </div>
-    </a>
   </div>
 </section>