have an ability to specify "base directory"

[jpengelbrecht]

Clear and concise description of the problem

currently if you build histoire in the index.html for example it has lines of code like , if for instance you want to host his as a sub directory on the same domain it currently breaks.

so for instance if you want to host your histoire on a url like /stories it will look for the above stylesheet in /assets instead of /stories/assets

Suggested solution

add a config property "base url". that allows this to be hosted as a sub domain which will append this value to the base directory.
so with a base url value of "/stories" the still import above becomes /stories/assets/style instead of /assets/style

Alternative

No response

Additional context

No response

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