Add Hash/History helper to handle offcanvas functionality

[GeoSot]

This PR is a first approach trying to make some UX improvements on Offcanvas plugin

It has been buzzing to my ears many times (mostly by designers), that Modals & Offcanvases in order to provide a better user experience, should react on browser history changes.

The simple requirement was : "Should close when the user goes back (swipe back / press back btn, etc)"

So as the #36604 was just another one trigger that shouted the same need

Main functionality:

• offcanvasInstance.show() => adds a hash on our browser address bar (window.location) & adds an entry to the browser's session history stack.
• offcanvasInstance.hide() => removes the hash from our address bar & replicates a history backward step
• if User change the hash on his/her address bar, and the hash matches to a component registered pattern, we call a callback where we can decide if we are going to handle. In the specific case, we toggle the offcanvas according to the hash existence. Cases:
  • when user goes back & forward,
  • if user adds/removes a hash
  • if User enters a link on his/her browser address bar and contains a hash

Preview:

https://deploy-preview-36648--twbs-bootstrap.netlify.app/docs/5.2/components/offcanvas/#bs-offcanvas-staticBackdrop

Needs:

• Feedback (programmatic & functional scope)
• tests (test new functionality, check existing)

closes #36647

Future applications:

• Modal can copy the same functionality.
• ScrollSpy may use it on smoothscroll
  ref:
  • Enabling smooth scroll option in Scroll Spy prevents url hash change #36387
  • Scrollspy: add history state in every click, when smoothScroll options, is activated #36402
• Tabs could be open (pretty sure we had an issue for this)
  ref:
  • Allow anchor links to automatically load JS tabs #25220
• Collapsibles could be triggered
  ref:
  • Show collapsed content when linking directly to #fragment #34299
• Tabs could be shown
  • Allow anchor links to automatically load JS tabs #25220

[damderhar]

Awesome! I've been hoping for this feature to be added for a while! Thanks so much for investing your time in this!