p2: add quote and code-block text formatting

web/src/components/MessageComposer.tsx

@@ -872,6 +872,31 @@ export function MessageComposer() {
     });
   }
 
+  function insertQuoteBlock() {
+    const textarea = textareaRef.current;
+    if (!textarea) {
+      return;
+    }
+    const start = textarea.selectionStart ?? text.length;
+    const end = textarea.selectionEnd ?? text.length;
+    const selected = text.slice(start, end);
+    const source = selected || "quote";
+    const quoted = source
+      .split("\n")
+      .map((line) => `> ${line}`)
+      .join("\n");
+    const nextValue = `${text.slice(0, start)}${quoted}${text.slice(end)}`;
+    setText(nextValue);
+    if (activeChatId) {
+      setDraft(activeChatId, nextValue);
+    }
+    requestAnimationFrame(() => {
+      textarea.focus();
+      const pos = start + quoted.length;
+      textarea.setSelectionRange(pos, pos);
+    });
+  }
+
   return (
     <div className="border-t border-slate-700/50 bg-slate-900/55 p-3">
       {activeChatId && replyToByChat[activeChatId] ? (
@@ -950,6 +975,12 @@ export function MessageComposer() {
           <button className="rounded px-2 py-1 text-xs hover:bg-slate-800" onClick={() => insertFormatting("`", "`")} type="button" title="Monospace">
             M
           </button>
+          <button className="rounded px-2 py-1 text-xs hover:bg-slate-800" onClick={() => insertFormatting("```\n", "\n```", "code")} type="button" title="Code block">
+            {"</>"}
+          </button>
+          <button className="rounded px-2 py-1 text-xs hover:bg-slate-800" onClick={insertQuoteBlock} type="button" title="Quote">
+            ❝
+          </button>
           <button className="rounded px-2 py-1 text-xs hover:bg-slate-800" onClick={insertLink} type="button" title="Link">
             🔗
           </button>

web/src/utils/formatMessage.tsx

@@ -108,5 +108,28 @@ function parseInline(text: string): string {
 }
 
 export function formatMessageHtml(text: string): string {
-  return parseInline(text);
+  const blocks: string[] = [];
+  const parts = text.split(/```/);
+  for (let i = 0; i < parts.length; i += 1) {
+    const part = parts[i];
+    const isCode = i % 2 === 1;
+    if (isCode) {
+      const value = escapeHtml(part.replace(/^\n+|\n+$/g, ""));
+      blocks.push(`<pre class="my-1 overflow-x-auto rounded-lg bg-slate-900/90 px-2 py-1.5 text-[12px]"><code>${value}</code></pre>`);
+      continue;
+    }
+    const lines = part.split("\n");
+    for (let lineIndex = 0; lineIndex < lines.length; lineIndex += 1) {
+      const line = lines[lineIndex];
+      if (line.startsWith("> ")) {
+        blocks.push(`<blockquote class="my-1 border-l-2 border-sky-400/80 bg-slate-800/60 px-2 py-1 text-sm">${parseInline(line.slice(2))}</blockquote>`);
+      } else {
+        blocks.push(parseInline(line));
+      }
+      if (lineIndex < lines.length - 1) {
+        blocks.push("<br/>");
+      }
+    }
+  }
+  return blocks.join("");
 }