Accept Proxmark dump uploads, mfc v2 JSON, and key.bin

Parse object-shaped mfc v2 dumps (the format Proxmark writes today) and
let the new-tag form upload dump.json/dump.bin plus an optional binary
hf-mf-*-key.bin instead of only pasting text.

tests/integration/api.test.ts

@@ -270,4 +270,38 @@ FFFFFFFFFFFFFF078069FFFFFFFFFFFF
     );
     expect(restore.status).toBe(200);
   });
+
+  it("imports Proxmark mfc v2 JSON dumps", async () => {
+    const auth = { Authorization: `Bearer ${bearer}` };
+    const siteRes = await postSite(
+      req("http://localhost/api/v1/sites", {
+        method: "POST",
+        headers: { ...auth, "Content-Type": "application/json" },
+        body: JSON.stringify({ code: "PM3", name: "Proxmark" }),
+      })
+    );
+    const site = await siteRes.json();
+    const dump = fs.readFileSync(
+      path.join(import.meta.dirname, "../fixtures/hf-mf-91A2F020-dump.json"),
+      "utf8"
+    );
+
+    const imported = await importTag(
+      req("http://localhost/api/v1/tags/import", {
+        method: "POST",
+        headers: { ...auth, "Content-Type": "application/json" },
+        body: JSON.stringify({
+          siteId: site.id,
+          label: "Proxmark v2",
+          content: dump,
+          filename: "hf-mf-91A2F020-dump.json",
+        }),
+      })
+    );
+    expect(imported.status).toBe(201);
+    const tag = await imported.json();
+    expect(tag.uid).toBe("91A2F020");
+    expect(tag.protocol).toBe("MIFARE_CLASSIC_1K");
+    expect(tag.keys.A[0]).toBe("A1D4FAFD4CAF");
+  });
 });