JSF: support custom component new URN namespace

[NicolaIsotta]

Update the JSF custom component wizard and metamodel to use "jakarta.faces.component" as the default tag namespace on Jakarta Faces projects while preserving "http://xmlns.jcp.org/jsf/component" for legacy JSF versions (3.0 and previous).

For reference:

• JSF 2.3 (javax package, old namespace) javadocs:
  https://jakarta.ee/specifications/faces/2.3/apidocs/javax/faces/component/facescomponent#namespace--
• Faces 3.0 (jakarta package, old namespace) javadocs:
  https://jakarta.ee/specifications/faces/3.0/apidocs/jakarta/faces/component/facescomponent#namespace()
• Faces 4.0 (jakarta package, new namespace) javadocs:
  https://jakarta.ee/specifications/faces/4.0/apidocs/jakarta/faces/component/facescomponent#namespace()

---

^Add meaningful description above

Click to collapse/expand PR instructions

By opening a pull request you confirm that, unless explicitly stated otherwise, the changes -

• are all your own work, and you have the right to contribute them.
• are contributed solely under the terms and conditions of the Apache License 2.0 (see section 5 of the license for more information).

LLMs, Commit messages and PR description:

• Please make sure (eg. git log) that all commits have a valid name and email address for you in the Author field.
• LLM assisted commits should be attributed with an Assisted-by: MODEL_NAME MODEL_VERSION line appended to the commit message.
  • Please mention coding assistance in the PR description too (eg. by adding the same Assisted-by line from above)
  • Please describe the changes in your own words - we'd like to know you understand the changes being made!

If you're a first time contributor, see the Contributing guidelines for more information.

If you're a committer, please label the PR before pressing "Create pull request" so that the right test jobs can run.

PR approval and merge checklist:

1. Was this PR correctly labeled, did the right tests run? When did they run?
2. Is this PR squashed?
3. Are author name / email address correct? Are co-authors correctly listed? Do the commit messages need updates?
4. Does the PR title and description still fit after the Nth iteration? Is the description sufficient to appear in the release notes?

If this PR targets the delivery branch: don't merge. (full wiki article)

[NicolaIsotta]

I'm marking thias as draft since the fix it's gonna be not as simple as I thought - Faces 3 has the jakarta package, but still relies on the old namespace: the new namespaces were introduced with Faces 4.

[NicolaIsotta]

Fixed now - we can get the default name space directly from the annotation, pretty elegant IMHO