Merge pull request #4307 from backstage/rugvip/devres

cli,config-loader,app-backend: fixes for module resolution and config loading

.changeset/loud-walls-collect.md

@@ -0,0 +1,5 @@
+---
+'@backstage/cli': patch
+---
+
+Fixed module resolution of external libraries during backend development. Modules used to be resolved relative to the backend entrypoint, but are now resolved relative to each individual module.

.changeset/neat-brooms-allow.md

@@ -0,0 +1,5 @@
+---
+'@backstage/config-loader': patch
+---
+
+Each piece of the configuration schema is now validated upfront, in order to produce more informative errors.

.changeset/nice-bottles-battle.md

@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-app-backend': patch
+---
+
+Failures to load the frontend configuration schema now throws an error that includes more context and instructions for how to fix the issue.