feat(frontend): render markdown in description and summary fields

- New shared MarkdownText component (react-markdown + remark-gfm)
  that renders links, bold, italic, lists, code, blockquotes.
  External links open in a new tab with rel=noopener.
- Applied to: technique description, threat actor description,
  test description, campaign description, detection rule descriptions,
  D3FEND defense descriptions, red/blue summaries and validation notes.
- procedure_text (code/commands) stays in <pre> — not processed as MD.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/src/components/MarkdownText.tsx

@@ -0,0 +1,108 @@
+/**
+ * MarkdownText — renders a markdown string as styled HTML.
+ *
+ * Uses react-markdown + remark-gfm (tables, strikethrough, etc.).
+ * External links always open in a new tab with rel="noopener noreferrer".
+ *
+ * Usage:
+ *   <MarkdownText content={technique.description} />
+ *   <MarkdownText content={test.red_summary} className="text-sm text-gray-400" />
+ */
+
+import ReactMarkdown from "react-markdown";
+import remarkGfm from "remark-gfm";
+import type { Components } from "react-markdown";
+
+interface MarkdownTextProps {
+  content: string | null | undefined;
+  /** Extra classes on the wrapper div */
+  className?: string;
+}
+
+const components: Components = {
+  // Links: always open external URLs in a new tab
+  a: ({ href, children, ...props }) => (
+    <a
+      href={href}
+      target="_blank"
+      rel="noopener noreferrer"
+      className="text-cyan-400 underline underline-offset-2 hover:text-cyan-300 transition-colors"
+      {...props}
+    >
+      {children}
+    </a>
+  ),
+  // Paragraphs: keep existing text colour, add spacing
+  p: ({ children }) => (
+    <p className="mb-2 last:mb-0 leading-relaxed">{children}</p>
+  ),
+  // Bold
+  strong: ({ children }) => (
+    <strong className="font-semibold text-gray-100">{children}</strong>
+  ),
+  // Italic
+  em: ({ children }) => (
+    <em className="italic text-gray-300">{children}</em>
+  ),
+  // Inline code
+  code: ({ children, className }) => {
+    const isBlock = className?.startsWith("language-");
+    if (isBlock) {
+      return (
+        <code className="block rounded-md bg-gray-800 px-3 py-2 font-mono text-xs text-gray-200 whitespace-pre-wrap">
+          {children}
+        </code>
+      );
+    }
+    return (
+      <code className="rounded bg-gray-800 px-1 py-0.5 font-mono text-xs text-cyan-300">
+        {children}
+      </code>
+    );
+  },
+  // Code blocks
+  pre: ({ children }) => (
+    <pre className="my-2 overflow-x-auto rounded-md bg-gray-800 p-3 text-xs">
+      {children}
+    </pre>
+  ),
+  // Unordered lists
+  ul: ({ children }) => (
+    <ul className="mb-2 list-disc pl-5 space-y-0.5">{children}</ul>
+  ),
+  // Ordered lists
+  ol: ({ children }) => (
+    <ol className="mb-2 list-decimal pl-5 space-y-0.5">{children}</ol>
+  ),
+  li: ({ children }) => <li className="leading-relaxed">{children}</li>,
+  // Headings (rarely appear in descriptions but handle them gracefully)
+  h1: ({ children }) => (
+    <h1 className="mb-2 text-base font-semibold text-white">{children}</h1>
+  ),
+  h2: ({ children }) => (
+    <h2 className="mb-1.5 text-sm font-semibold text-white">{children}</h2>
+  ),
+  h3: ({ children }) => (
+    <h3 className="mb-1 text-sm font-medium text-gray-200">{children}</h3>
+  ),
+  // Blockquotes
+  blockquote: ({ children }) => (
+    <blockquote className="my-2 border-l-2 border-cyan-500/40 pl-3 text-gray-400 italic">
+      {children}
+    </blockquote>
+  ),
+  // Horizontal rule
+  hr: () => <hr className="my-3 border-gray-700" />,
+};
+
+export default function MarkdownText({ content, className }: MarkdownTextProps) {
+  if (!content) return null;
+
+  return (
+    <div className={className}>
+      <ReactMarkdown remarkPlugins={[remarkGfm]} components={components}>
+        {content}
+      </ReactMarkdown>
+    </div>
+  );
+}

frontend/src/components/test-detail/TeamTabs.tsx

@@ -1,5 +1,6 @@
 import { useState } from "react";
 import { useQuery } from "@tanstack/react-query";
+import MarkdownText from "../MarkdownText";
 import {
   Shield,
   ShieldCheck,
@@ -205,7 +206,7 @@ export default function TeamTabs({
             placeholder="Summarize the Red Team findings..."
           />
         ) : (
-          <p className="text-sm text-gray-400">{test.red_summary || "No summary yet."}</p>
+          <MarkdownText content={test.red_summary || "No summary yet."} className="text-sm text-gray-400" />
         )}
       </div>
 
@@ -250,7 +251,7 @@ export default function TeamTabs({
             </span>
           </div>
           {test.red_validation_notes && (
-            <p className="mt-2 text-sm text-gray-400">{test.red_validation_notes}</p>
+            <MarkdownText content={test.red_validation_notes} className="mt-2 text-sm text-gray-400" />
           )}
         </div>
       )}
@@ -317,7 +318,7 @@ export default function TeamTabs({
             placeholder="Summarize the Blue Team analysis..."
           />
         ) : (
-          <p className="text-sm text-gray-400">{test.blue_summary || "No summary yet."}</p>
+          <MarkdownText content={test.blue_summary || "No summary yet."} className="text-sm text-gray-400" />
         )}
       </div>
 
@@ -424,7 +425,7 @@ export default function TeamTabs({
             </span>
           </div>
           {test.blue_validation_notes && (
-            <p className="mt-2 text-sm text-gray-400">{test.blue_validation_notes}</p>
+            <MarkdownText content={test.blue_validation_notes} className="mt-2 text-sm text-gray-400" />
           )}
         </div>
       )}
@@ -461,7 +462,7 @@ export default function TeamTabs({
             </div>
             <div>
               <dt className="text-xs font-medium uppercase text-gray-500">Summary</dt>
-              <dd className="mt-0.5 text-sm text-gray-300">{test.red_summary || "N/A"}</dd>
+              <dd className="mt-0.5"><MarkdownText content={test.red_summary || "N/A"} className="text-sm text-gray-300" /></dd>
             </div>
             <div>
               <dt className="text-xs font-medium uppercase text-gray-500">Evidence Files</dt>
@@ -512,7 +513,7 @@ export default function TeamTabs({
             </div>
             <div>
               <dt className="text-xs font-medium uppercase text-gray-500">Summary</dt>
-              <dd className="mt-0.5 text-sm text-gray-300">{test.blue_summary || "N/A"}</dd>
+              <dd className="mt-0.5"><MarkdownText content={test.blue_summary || "N/A"} className="text-sm text-gray-300" /></dd>
             </div>
             <div>
               <dt className="text-xs font-medium uppercase text-gray-500">Evidence Files</dt>

frontend/src/pages/CampaignDetailPage.tsx

@@ -1,5 +1,6 @@
 import { useState } from "react";
 import { useParams, useNavigate } from "react-router-dom";
+import MarkdownText from "../components/MarkdownText";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import {
   Loader2,
@@ -236,7 +237,7 @@ export default function CampaignDetailPage() {
                 </span>
               </div>
               {campaign.description && (
-                <p className="mt-1 text-sm text-gray-400">{campaign.description}</p>
+                <MarkdownText content={campaign.description} className="mt-1 text-sm text-gray-400" />
               )}
               <div className="mt-2 flex flex-wrap items-center gap-3 text-xs text-gray-500">
                 {campaign.threat_actor_name && (

frontend/src/pages/TechniqueDetailPage.tsx

@@ -1,5 +1,6 @@
 import { useState } from "react";
 import { useParams, useNavigate } from "react-router-dom";
+import MarkdownText from "../components/MarkdownText";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import {
   Loader2,
@@ -182,9 +183,10 @@ export default function TechniqueDetailPage() {
         {/* Description */}
         <div className="lg:col-span-2 rounded-xl border border-gray-800 bg-gray-900 p-6">
           <h2 className="mb-3 text-lg font-semibold text-white">Description</h2>
-          <p className="text-sm text-gray-400 leading-relaxed whitespace-pre-wrap">
-            {technique.description || "No description available."}
-          </p>
+          <MarkdownText
+            content={technique.description || "No description available."}
+            className="text-sm text-gray-400 leading-relaxed"
+          />
         </div>
 
         {/* Metadata */}
@@ -579,7 +581,7 @@ function DetectionRulesSection({ rules }: { rules: DetectionRule[] }) {
                     onClick={(e) => e.stopPropagation()}
                   >
                     {rule.description && (
-                      <p className="text-xs text-gray-400 leading-relaxed">{rule.description}</p>
+                      <MarkdownText content={rule.description} className="text-xs text-gray-400 leading-relaxed" />
                     )}
                     <div className="flex flex-wrap gap-3 text-xs text-gray-500">
                       {rule.rule_format && (
@@ -702,7 +704,7 @@ function D3FENDSection({ defenses }: { defenses: Array<{
                   {isExpanded && (
                     <div className="mt-3 space-y-2 border-t border-gray-700/50 pt-3">
                       {def.description ? (
-                        <p className="text-xs text-gray-300 leading-relaxed">{def.description}</p>
+                        <MarkdownText content={def.description} className="text-xs text-gray-300 leading-relaxed" />
                       ) : (
                         <p className="text-xs text-gray-500 italic">No description available.</p>
                       )}

frontend/src/pages/TestDetailPage.tsx

@@ -1,4 +1,5 @@
 import { useParams, useNavigate } from "react-router-dom";
+import MarkdownText from "../components/MarkdownText";
 import { useQuery, useMutation, useQueryClient } from "@tanstack/react-query";
 import { useState, useEffect, useCallback } from "react";
 import { Loader2, AlertCircle, ArrowLeft } from "lucide-react";
@@ -441,8 +442,8 @@ export default function TestDetailPage() {
             <dl className="space-y-4">
               <div>
                 <dt className="text-xs font-medium uppercase text-gray-500">Description</dt>
-                <dd className="mt-1 text-sm text-gray-300">
-                  {test.description || "\u2014"}
+                <dd className="mt-1">
+                  <MarkdownText content={test.description || "\u2014"} className="text-sm text-gray-300" />
                 </dd>
               </div>
               <div>

frontend/src/pages/ThreatActorDetailPage.tsx

@@ -1,4 +1,5 @@
 import { useParams, useNavigate } from "react-router-dom";
+import MarkdownText from "../components/MarkdownText";
 import { useQuery } from "@tanstack/react-query";
 import {
   Loader2,
@@ -263,9 +264,7 @@ export default function ThreatActorDetailPage() {
           <h2 className="mb-3 text-sm font-semibold uppercase tracking-wider text-gray-500">
             Description
           </h2>
-          <p className="text-sm leading-relaxed text-gray-300 whitespace-pre-line">
-            {actor.description}
-          </p>
+          <MarkdownText content={actor.description} className="text-sm leading-relaxed text-gray-300" />
         </div>
       )}