The docsite path was being initialized as a global variable. This wasn't
an issue before we were caching and unsetting the env vars, but now that
`wavebase.GetWaveAppPath()` returns the contents of the cached variable,
we need to read its value at runtime, since it won't be set at the time
the global variable is initialized.
This adds a custom resolver to the docsite server to fall back to .html
addresses when it gets a not found for a given path. This fixes an issue
where subpages would return a 404 after a hard reload of the frontend. I
also added an effect that will run on startup to resolve the latest
docsite url and set it in the metadata, since the backend port changes
on every run of the app. I also made it so that setting the default
homepage in the webview widget will also unset any block-specific
homepage.
This will take the latest artifact from the waveterm-docs repo and embed
it in the app binary. When the help view is launched, it will be served
from our backend. If the embedded copy doesn't exist, such as in
unpackaged versions of the app or in locally packaged versions, it will
use the hosted site instead.
There is a sibling PR in the docs repository to build the embedded
version of the app (strips out some external links, removes Algolia
DocSearch, updates the baseUrl)
https://github.com/wavetermdev/waveterm-docs/pull/46
