Build: Fix failing CSS asset paths (#95380)

* build(webpack): set publicpath and process urls to resolve assets correctly

* build(webpack): add back --progress to build

* Add local cdn

(cherry picked from commit 7a19523fa476fd5ff2d7669d116f5be462b100f5)

* chore(devenv): fix local_cdn path in ngnix conf

* chore(codeowners): add frontend-ops as owners of local_cdn docker block

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Co-authored-by: Andreas Christou <andreas.christou@grafana.com>

scripts/webpack/webpack.dev.js

@@ -74,7 +74,7 @@ module.exports = (env = {}) => {
         },
         require('./sass.rule.js')({
           sourceMap: false,
-          preserveUrl: false,
+          preserveUrl: true,
         }),
       ],
     },