📈(frontend) track errors when starting or stopping a recording

Send an analytics event whenever starting or stopping a recording
fails, so we can monitor how often it happens.

It also gives support the context needed to understand what went
wrong when inspecting a user's session.

CHANGELOG.md

@@ -8,6 +8,10 @@ and this project adheres to
 
 ## [Unreleased]
 
+### Added
+
+- 📈(frontend) track errors when starting or stopping a recording
+
 ### Changed
 
 - ✨(backend) accept form-urlencoded on the user token endpoint