Since #20218 introduced internal watching template, template watching
should be removed from `air`. This will prevent restart the whole server
once the template files changed to speed up developing when using `make
watch`.
To ensure `make watch` will reuse template watching, this PR introduced
a new ENV `GITEA_RUN_MODE` to make sure `make watch` will always run in
a dev mode of Gitea so that template watching will open.
This PR also added more exclude testdata directories.
* Add 'watch-backend'
This leverages `air` to watch the backend files and trigger `make
backend` automatically when they change. It seems to work rather well
together with `watch-frontend`.
Fixes: https://github.com/go-gitea/gitea/issues/12318
* rework docs to a new section for continuous build
Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Lunny Xiao
Gusted
silverwind