* feat: add extensions to the backend plugin model
* feat: update the frontend plugin types
* feat(pluginContext): return a `null` if there is no context found
This will be necessary to understand if a certain hook is running inside a plugin context or not.
* feat: add utility functions for checking extension configs
* tests: fix failing tests due to the type updates
* feat(AddedComponentsRegistry): validate plugin meta-info
* feat(AddedLinksRegistry): validate meta-info
* feat(ExposedComponentsRegistry): validate meta-info
* feat(usePluginComponent): add meta-info validation
* feat(usePluginComponents): add meta-info validation
* feat(usePluginLinks): add meta-info validation
* fix: only validate meta-info in registries if dev mode is enabled
* tests: add unit tests for the restrictions functionality
* tests: fix Go tests
* fix(tests): revert accidental changes
* fix: run goimports
* fix: api tests
* add nested app so that meta data can bested e2e tested
* refactor(types): extract the ExtensionInfo into a separate type
* refactor(extensions/utils): use Array.prototype.some() instead of .find()
* refactor(usePluginLinks): update warning message
* feat(usePluginExtensions()): validate plugin meta-info
* Wip
* fix(e2e): E2E tests for extensions
* fix(extensions): allow multiple "/" slashes in the extension point id
* fix(extensions/validators): stop validating the plugin id pattern
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Co-authored-by: Erik Sundell <erik.sundell87@gmail.com>