Preserve full sub-path when switching projects

[lorumic]

Done

• Improved the function to keep the context when switching project. Now the full sub-path is kept, allowing to preserve also the tab context of the "Storage" page.

QA

1. Run the LXD-UI:
   • On the demo server via the link posted by @webteam-app below. This is only available for PRs created by collaborators of the repo. Ask @lorumic or @edlerd for access.
   • With a local copy of this branch, run as described here.
2. Perform the following QA steps:
   • Visit "Storage" page, change tab, e.g. to "Volumes"
   • Switch project using the project selector in the side nav, and check that the tab context is preserved
   • Ensure that switching project from any page works as expected

[webteam-app]

Demo starting at https://lxd-ui-509.demos.haus

[edlerd]

It works now as expected. Some ideas to simplify below.

[edlerd]

very good