Dispatch custom event on native and tiny events

[madeInLagny]

Catching events in the current setup is tricky using some javascript frameworks (ie Lit-html). Adding stardard

this.dispatchEvent(
          new CustomEvent("eventName", {
            bubbles: true,
            composed: true,
          }))

would make the implementation easier to integrate.
Note that a editor-ready event is also useful to catch considering time lag between element initiation and editor ready state.

[exalate-issue-sync]

Ref: INT-2626