feat(analytics): Goatcounter support (#956)

* Add options to support goatcounter analytics

* goatcounter: support self-hosted

* Add to configuration docs for goatcounter settings

* use https instead of protocol-relative link for goatcounter js

quartz/plugins/emitters/componentResources.ts

@@ -126,6 +126,15 @@ function addGlobalPageResources(
 
       document.head.appendChild(umamiScript)
     `)
+  } else if (cfg.analytics?.provider === "goatcounter") {
+    componentResources.afterDOMLoaded.push(`
+      const goatcounterScript = document.createElement("script")
+      goatcounterScript.src = "${cfg.analytics.scriptSrc ?? "https://gc.zgo.at/count.js"}"
+      goatcounterScript.async = true
+      goatcounterScript.setAttribute("data-goatcounter",
+        "https://${cfg.analytics.websiteId}.${cfg.analytics.host ?? "goatcounter.com"}/count")
+      document.head.appendChild(goatcounterScript)
+    `)
   }
 
   if (cfg.enableSPA) {