Add busy indication (#4040)

* First pass at a proper state machine for managing output progress state

* `yarn build` (GitHub Actions)

* Add useBusyIndicators(), spinnerOptions(), and pulseOptions()

* Bring in new spinner defaults

* Use an actual div instead of a pseudo-element since chromium can't be trusted to show them when animated

* Revert "Use an actual div instead of a pseudo-element since chromium can't be trusted to show them when animated"

This reverts commit 6167c1dfd7.

* Embed animation inside svg (to avoid Chromium bug). Consolidate options into a singular busyIndicatorOptions()

* Add to pkgdown reference

* `devtools::document()` (GitHub Actions)

* `yarn build` (GitHub Actions)

* Bump version

* `yarn build` (GitHub Actions)

* Sync package version (GitHub Actions)

* Apply suggestions from code review

Co-authored-by: Garrick Aden-Buie <garrick@adenbuie.com>

* Update snapshots

* `devtools::document()` (GitHub Actions)

* Address feedback

* Bring in more spinner type options

* fix use of fs

* Code review

* `devtools::document()` (GitHub Actions)

* Sync package version (GitHub Actions)

* Update snapshots

* Fix comments

* Make snapshot consistent cross-platform

* Fix namespace issue

* Reduce specificity of position relative

* Skip snapshot on windows; update news

* Whoops

* Scope spinner customizations to parent element by default

* Update snapshots

* Reorder spinner types

* Set a private random seed in tests

* Better id naming

---------

Co-authored-by: cpsievert <cpsievert@users.noreply.github.com>
Co-authored-by: Garrick Aden-Buie <garrick@adenbuie.com>

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: shiny
 Type: Package
 Title: Web Application Framework for R
-Version: 1.8.1.9000
+Version: 1.8.1.9001
 Authors@R: c(
     person("Winston", "Chang", role = c("aut", "cre"), email = "winston@posit.co", comment = c(ORCID = "0000-0002-1576-2126")),
     person("Joe", "Cheng", role = "aut", email = "joe@posit.co"),
@@ -128,6 +128,8 @@ Collate:
     'map.R'
     'utils.R'
     'bootstrap.R'
+    'busy-indicators-spinners.R'
+    'busy-indicators.R'
     'cache-utils.R'
     'deprecated.R'
     'devmode.R'