feat: add flag to disable template insights (#20940)

Closes #20399 

To summarize the original commit messages:

- Do not log stats to the database.
- Return errors on the insight endpoints.
- Update the frontend to show those errors.
- Also fixes an issue with getting the user status count via codersdk,
since I added a test to ensure it was not disabled by this flag and it
was sending the wrong payload.

coderd/apidoc/docs.go

@@ -14347,6 +14347,9 @@ const docTemplate = `{
                 "telemetry": {
                     "$ref": "#/definitions/codersdk.TelemetryConfig"
                 },
+                "template_insights": {
+                    "$ref": "#/definitions/codersdk.TemplateInsightsConfig"
+                },
                 "terms_of_service_url": {
                     "type": "string"
                 },
@@ -18596,6 +18599,14 @@ const docTemplate = `{
                 }
             }
         },
+        "codersdk.TemplateInsightsConfig": {
+            "type": "object",
+            "properties": {
+                "enable": {
+                    "type": "boolean"
+                }
+            }
+        },
         "codersdk.TemplateInsightsIntervalReport": {
             "type": "object",
             "properties": {