handle dates as tags

package.json

@@ -40,6 +40,7 @@
     "hast-util-to-jsx-runtime": "^1.2.0",
     "hast-util-to-string": "^2.0.0",
     "is-absolute-url": "^4.0.1",
+    "js-yaml": "^4.1.0",
     "mdast-util-find-and-replace": "^2.2.2",
     "mdast-util-to-string": "^3.2.0",
     "micromorph": "^0.4.5",
@@ -74,6 +75,7 @@
     "@types/d3": "^7.4.0",
     "@types/flexsearch": "^0.7.3",
     "@types/hast": "^2.3.4",
+    "@types/js-yaml": "^4.0.5",
     "@types/node": "^20.1.2",
     "@types/pretty-time": "^1.1.2",
     "@types/serve-handler": "^6.1.1",