Revert "build: finish replacing paver assets (#34554)" (#34700)

Reverts #34554, which causes compilation of edX.org's
legacy comprehensive theme to be skipped in their deployment pipeline.
We have not determined the precise cause yet, but it seems like the
compile_sass management command is not correctly getting the
list of comprehensive theme directories from Django settings.

scripts/compile_sass.py

@@ -67,12 +67,14 @@ NORMALIZED_ENVS = {
     "theme_dirs",
     metavar="PATH",
     multiple=True,
-    envvar="COMPREHENSIVE_THEME_DIRS",
-    type=click.Path(path_type=Path),
+    envvar="EDX_PLATFORM_THEME_DIRS",
+    type=click.Path(
+        exists=True, file_okay=False, readable=True, writable=True, path_type=Path
+    ),
     help=(
         "Consider sub-dirs of PATH as themes. "
         "Multiple theme dirs are accepted. "
-        "If none are provided, we look at colon-separated paths on the COMPREHENSIVE_THEME_DIRS env var."
+        "If none are provided, we look at colon-separated paths on the EDX_PLATFORM_THEME_DIRS env var."
     ),
 )
 @click.option(

scripts/watch_sass.sh

@@ -4,11 +4,11 @@
 # Invoke from repo root as `npm run watch-sass`.
 
 # By default, only watches default Sass.
-# To watch themes too, provide colon-separated paths in the COMPREHENSIVE_THEME_DIRS environment variable.
+# To watch themes too, provide colon-separated paths in the EDX_PLATFORM_THEME_DIRS environment variable.
 # Each path will be treated as a "theme dir", which means that every immediate child directory is watchable as a theme.
 # For example:
 #
-#   COMPREHENSIVE_THEME_DIRS=/openedx/themes:./themes npm run watch-sass
+#   EDX_PLATFORM_THEME_DIRS=/openedx/themes:./themes npm run watch-sass
 #
 # would watch default Sass as well as /openedx/themes/indigo, /openedx/themes/mytheme, ./themes/red-theme, etc.