Add overflow-safe tooltips and update styles

[AlanSl]

This mainly adds tooltips to the SDK with examples for PeerIds and the Timeline...

• [x] Add generic tooltip
• [x] Add tick arrow pointing to what it refers to
• [x] Support top, left, right, bottom orientation, centring by default
• [x] Ensure styles can be easily and consistently overridden
• [x] Apply to peer Ids in connection table, following designs
• [x] Apply to timeline, always visible

...including a feature to ensure they don't overflow a specified container:

• [x] Ensure tooltips don't overflow container
• [x] Make container specifiable
• [x] Make component or shell root containers available everywhere via context
• [x] Ensure timeline tooltip doesn't overflow timeline element
• [x] Ensure peerId tooltip doesn't overflow component view area using context

It also updates many styles to be closer to the designs and fixes a few bugs:

• [x] Fix regression where mouseovers of areas in timeline visualisation stopped highlighting
• [x] Fix various React warnings
• [x] Improve colours and typography
• [x] Add status chips to connections table

Example:

Examples of the tooltips automatically offsetting themselves to stay in the bounds of their specified container:

[AlanSl]

Just pushing a couple of fixes for small bugs

[AlanSl]

I'm just cherry-picking over a couple of commits that fixed some small style regressions that were visible in the staging build of the catalogue.