Get rid of obsolete /search/hashtag page

@Tirokk there is this neat URL module: https://nodejs.org/api/url.html

It has convenience methods for adding query params. I'm just not quite
sure about browser compatibility though.

webapp/components/Editor/Editor.vue

@@ -491,6 +491,8 @@ export default {
     // we have to replace our suggestion text with a mention
     // so it's important to pass also the position of your suggestion text
     selectItem(item) {
+      const searchUrl = new URL('/')
+      searchUrl.searchParams.set('hashtag', item.name)
       const typeAttrs = {
         mention: {
           // TODO: use router here
@@ -499,7 +501,7 @@ export default {
         },
         hashtag: {
           // TODO: Fill up with input hashtag in search field
-          url: `/search/hashtag/${item.name}`,
+          url: searchUrl.href,
           label: item.name,
         },
       }

webapp/components/FilterMenu/FilterMenu.vue

@@ -49,7 +49,7 @@
 export default {
   props: {
     user: { type: Object, required: true },
-    hashtag: { type: Object, default: null },
+    hashtag: { type: String, default: null },
   },
   data() {
     return {

webapp/pages/search/hashtag/_id.vue

@@ -1,12 +0,0 @@
-<template>
-  <div></div>
-</template>
-
-<script>
-export default {
-  mounted() {
-    const { id: hashtag } = this.$route.params
-    this.$router.push({ path: '/', query: { hashtag } })
-  },
-}
-</script>