#### improve export spinner
update at least once a minute in non-tty
update progress regularly when using the spinner
decrease frequency of the spinner (windows console output is expensive)
#### restart static page generation and collecting page data worker pools when hanging
when for 1 minute no activity happens on the worker pool, restart it
log a warning for hanging jobs
#### add page generation duration to summary tree
![image](https://user-images.githubusercontent.com/1365881/125750454-8845f1b1-faf0-4598-b7a4-ea796b884691.png)
for `[+n more pages]` is will show `(avg 321 ms)` when the average is over the threshold.
It will allocate 8 lines for preview pages (instead of 4) when they contain slow pages
## Feature
- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [x] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [x] Errors have helpful link attached, see `contributing.md`
## Documentation / Examples
- [ ] Make sure the linting passes