Complete GFM support: tables, task lists, strikethrough

Editor: add tablePlugin so markdown tables round-trip and render. Task
lists (`- [ ]`), strikethrough, code (inline + fenced), headings, lists,
quotes, and links already work via listsPlugin/core/markdownShortcut. CSS:
suppress the disc bullet on task-list items (they draw their own checkbox)
and style tables.

Display: render task-list checkboxes (no stray bullet), GFM tables, and
strikethrough so the read view matches what the editor produces.

https://claude.ai/code/session_019DU6V5z6Nr4Vu7b1fBDnq4

js/desktop/src/features/compose/markdown-editor.css

@@ -108,6 +108,10 @@
   margin-bottom: 0.25rem;
   line-height: 1.625;
 }
+/* Task-list items draw their own checkbox — no disc bullet. */
+.llink-mdx-content li[class*="_listItem"] {
+  list-style: none;
+}
 
 /* Blockquote */
 .llink-mdx-content blockquote {
@@ -132,3 +136,20 @@
   border: none;
   border-top: 1px solid rgb(255 255 255 / 0.1);
 }
+
+/* Tables */
+.llink-mdx-content table {
+  margin-bottom: 0.75rem;
+  border-collapse: collapse;
+  width: auto;
+}
+.llink-mdx-content th,
+.llink-mdx-content td {
+  border: 1px solid rgb(255 255 255 / 0.2);
+  padding: 0.375rem 0.625rem;
+  text-align: left;
+}
+.llink-mdx-content th {
+  background: rgb(255 255 255 / 0.08);
+  font-weight: 600;
+}

js/desktop/src/features/compose/markdown-editor.tsx

@@ -9,6 +9,7 @@ import {
   linkPlugin,
   codeBlockPlugin,
   codeMirrorPlugin,
+  tablePlugin,
   markdownShortcutPlugin,
 } from "@mdxeditor/editor";
 import "@mdxeditor/editor/style.css";
@@ -90,6 +91,10 @@ export function MarkdownEditor({
         linkPlugin({ disableAutoLink: true }),
         codeBlockPlugin({ defaultCodeBlockLanguage: "" }),
         codeMirrorPlugin({ codeBlockLanguages: CODE_BLOCK_LANGUAGES }),
+        tablePlugin(),
+        // Headings, lists (incl. `- [ ]` task lists), emphasis, strikethrough,
+        // inline code, quotes, and links all transform as you type via these
+        // shortcuts; fenced code blocks and tables are inserted via paste/import.
         markdownShortcutPlugin(),
       ]}
     />

js/desktop/src/features/particles/text-particle-view.tsx

@@ -95,14 +95,55 @@ const markdownComponents: React.ComponentProps<typeof ReactMarkdown>["components
       {children}
     </pre>
   ),
-  ul: ({ children }) => <ul className="mb-3 list-disc pl-5 text-white last:mb-0">{children}</ul>,
+  del: ({ children }) => <del className="text-white/70 line-through">{children}</del>,
+  ul: ({ className, children }) => (
+    <ul
+      className={cn(
+        "mb-3 text-white last:mb-0",
+        className?.includes("contains-task-list") ? "list-none pl-0" : "list-disc pl-5",
+      )}
+    >
+      {children}
+    </ul>
+  ),
   ol: ({ children }) => <ol className="mb-3 list-decimal pl-5 text-white last:mb-0">{children}</ol>,
-  li: ({ children }) => <li className="mb-1 leading-relaxed">{children}</li>,
+  li: ({ className, children }) => (
+    <li
+      className={cn(
+        "mb-1 leading-relaxed",
+        className?.includes("task-list-item") && "flex list-none items-start gap-2",
+      )}
+    >
+      {children}
+    </li>
+  ),
+  input: ({ type, checked }) =>
+    type === "checkbox" ? (
+      <input
+        type="checkbox"
+        checked={!!checked}
+        readOnly
+        className="mt-1.5 size-3.5 shrink-0 accent-blue-500"
+      />
+    ) : null,
   blockquote: ({ children }) => (
     <blockquote className="mb-3 border-l-2 border-white/30 pl-4 italic text-white/70 last:mb-0">
       {children}
     </blockquote>
   ),
+  table: ({ children }) => (
+    <div className="mb-3 overflow-x-auto last:mb-0">
+      <table className="w-auto border-collapse text-sm text-white">{children}</table>
+    </div>
+  ),
+  th: ({ children }) => (
+    <th className="border border-white/20 bg-white/10 px-2.5 py-1.5 text-left font-semibold">
+      {children}
+    </th>
+  ),
+  td: ({ children }) => (
+    <td className="border border-white/20 px-2.5 py-1.5">{children}</td>
+  ),
   hr: () => <hr className="my-4 border-white/10" />,
 };