There is a delay between the page being loaded and the bridge being ready to use. During that delay, the user might be sent to Wikidata when the click the link. In order to provide the best experience for our users, that delay should be as short as reasonably possible.
To ensure consistently high performance we need to track it, so we can notice, investigate and resolve unsatisfactory levels of performance.

Acceptance criteria:

Track in Grafana the 75th, 95th and 99th percentile for the following two metrics:

• time from page load to link listener being attached
• time between link clicked and modal opened (this becomes relevant with T235765: immediate kicking in of the Bridge: Attach link listeners sooner)