feat(frontend): add Open Graph and social preview tags (closes #169)

PROGRESS.md

@@ -319,3 +319,11 @@ is closed — see [CONTRIBUTING.md](CONTRIBUTING.md).
 - **By:** ALLEN-AYODEJI
 - **Closes:** N/A
 - **Status:** Merged.
+
+### frontend — Open Graph and social preview tags
+
+- **What:** Added `og:*` / Twitter card meta tags to `frontend/index.html` and
+  generated `frontend/public/og-image.png` (1200×630) from `assets/banner.svg`.
+- **By:** kevindurant735rocket-creator
+- **Closes:** #169
+- **Status:** `npm run lint`, `typecheck`, `test` (21 tests) and `build` pass.

frontend/index.html

@@ -7,6 +7,17 @@
     <meta name="theme-color" content="#060a14" />
     <title>DepRadar — Bounty Dashboard</title>
     <meta name="description" content="Read-only dashboard for DepRadar supply-chain security bounties on Stellar." />
+    <meta property="og:type" content="website" />
+    <meta property="og:title" content="DepRadar — Bounty Dashboard" />
+    <meta property="og:description" content="Read-only dashboard for DepRadar supply-chain security bounties on Stellar." />
+    <meta property="og:image" content="/og-image.png" />
+    <meta property="og:image:width" content="1200" />
+    <meta property="og:image:height" content="630" />
+    <meta property="og:url" content="https://dep-radar.example/" />
+    <meta name="twitter:card" content="summary_large_image" />
+    <meta name="twitter:title" content="DepRadar — Bounty Dashboard" />
+    <meta name="twitter:description" content="Read-only dashboard for DepRadar supply-chain security bounties on Stellar." />
+    <meta name="twitter:image" content="/og-image.png" />
   </head>
   <body>
     <div id="root"></div>