Extension registry client API

[aloubyansky]

This PR:

• switches the devtools from the legacy QuarkusPlatformDescriptor based API to the new ExtensionCatalog API;
• introduces the registry client API and switches Maven and Gradle plaugins and the CLI to use the registry client to resolve the catalog;
• changes the platform descriptor JSON format.

Until the default community registry service is available I implemented a fallback to resolving the platform descriptors directly from the BOM coordinates.

Fixes #12422

[gsmet]

Until the default community registry service is available I implemented a fallback to resolving the platform descriptors directly from the BOM coordinates.

Small comment on this: I think you will need to keep the fallback around. It's not obvious people will be able to access the registry in corporate environments (a lot of corporate environments have exceptions for Maven Central from what I saw these past months in user comments).

Just approved the change, not reviewed the full PR yet

[aloubyansky]

Until the default community registry service is available I implemented a fallback to resolving the platform descriptors directly from the BOM coordinates.

Small comment on this: I think you will need to keep the fallback around. It's not obvious people will be able to access the registry in corporate environments (a lot of corporate environments have exceptions for Maven Central from what I saw these past months in user comments).

Interestingly, one of the reasons to use the Maven backend/interface was to make it easily/easier available in corporate environments. If our tools will end being limited to the platform extensions in (many) corp.env. or be painful to configure we should re-consider the approach. One way to make it available OOTB would be to publish the non-platform extension catalogs to the Maven Central repo.

[gastaldi]

I reviewed the changes on each of the 277 files impacted by this PR and they look decent. I request a couple of small changes though.

I have one suggestion: it would be nice to have a quarkus-devtools-registry-spi module containing the SPI classes required to be implemented in the server side of a Registry (eg. the registry.quarkus.io app)

[aloubyansky]

I have one suggestion: it would be nice to have a quarkus-devtools-registry-spi module containing the SPI classes required to be implemented in the server side of a Registry (eg. the registry.quarkus.io app)

This PR doesn't really include anything that should be implemented on the server side. So, the module would be empty.

[gastaldi]

Rebased since it introduced conflicts with 0d0bd91

[gastaldi]

LGTM