[Bug] Update URL after checkout branch

MRs:

• Update URL after branch checkout (!327 - merged)
• Web IDE: handle context updated event (gitlab!157320 - merged)

Description

With feat: Checkout branch (!144 - merged) we can now change branches, but there's a known UX issue:

The URL of the Web IDE tab is currently not updated when the user changes branches.

Implementation plan

• See implementation plan for #109 (closed)