FEATURE: topic_view_stats table with daily fidelity (#27197)

This gives us daily fidelity of topic view stats

New table stores a row per topic viewed per day tracking
anonymous and logged on views

We also have a new endpoint `/t/ID/views-stats.json` to get the statistics for the topic.

app/controllers/topic_view_stats_controller.rb

@@ -0,0 +1,35 @@
+# frozen_string_literal: true
+
+class TopicViewStatsController < ApplicationController
+  MAX_STATS_PER_API_REQUEST = 300
+
+  def index
+    topic = Topic.find(params[:topic_id].to_i)
+    guardian.ensure_can_see!(topic)
+
+    from = 30.days.ago.to_date
+    to = Date.today
+
+    begin
+      from = params[:from].to_date if params[:from].present?
+      to = params[:to].to_date if params[:to].present?
+    rescue Date::Error
+      render_json_error(I18n.t("topic_view_stats.invalid_date"), status: 422)
+      return
+    end
+
+    stats =
+      TopicViewStat
+        .where(topic_id: topic.id, viewed_at: from..to)
+        .order(viewed_at: :desc)
+        .limit(MAX_STATS_PER_API_REQUEST)
+
+    rows = []
+
+    stats.each do |stat|
+      rows << { viewed_at: stat.viewed_at, views: stat.anonymous_views + stat.logged_in_views }
+    end
+
+    render json: { topic_id: topic.id, stats: rows.reverse }
+  end
+end