Indicate if a published/hosted shareable viz url is outdated

[stephkaiser]

Description

When users retrieve a published shareable-viz url in kedro-viz, there is currently no way to tell if the url is outdated to their current local version, unless users keep track of the timestamp and remember whether or not they've made changes after that.

Context (#1851)

This was actually one of the most requested feature when I did usability testing for shareable viz, almost every user I tested with asked for this so we do have some evidence that there is a user need and potential pain point. Since it's a large technical effort, let's discuss potential ways we can make this smaller in scope - for example, we don't need a comparison here just a signal to users that it's time for them to republish as their current url is outdated. This is also relatively low-priority as shareable-viz is quite a new feature, we'd like to see numbers for adoption of the feature first before building upon it.

Possible Implementation

@Huongg had a discussion with the engineering team and below is the potential suggestion for this feature:

(Also requires further design brainstorming and exploration)

[rashidakanchwala]

One potential solution could be putting the 'last published date' information in the '.viz' folder of a user's kedro project and retrieving that to compare against the new publish date.

.viz folder PR - #1915