feat(build): deploy to maven.codelibs.org

[marevol]

Summary

Maven Central introduced an upload limit that makes it impractical to keep releasing the Fess
plugin artifacts there, so the plugins move to the CodeLibs repository. fess-parent, fess,
fess-crawler, fess-crawler-playwright and fess-suggest stay on Maven Central.

Why this is declared per plugin rather than in fess-parent

distributionManagement is inherited unconditionally and a POM cannot exempt itself from what
it declares. Declaring the CodeLibs repositories in fess-parent therefore also redirected the
SNAPSHOT deployments of the five projects that stay on Maven Central, because
central-publishing-maven-plugin resolves SNAPSHOT deployments through
project.getDistributionManagementArtifactRepository() and only falls back to
centralSnapshotsUrl when it is absent. See codelibs/fess-parent#62.

Why scpexe rather than scp

The transport comes from the wagon-ssh-external build extension inherited from
fess-parent, which delegates to the platform SSH client. The embedded alternative,
wagon-ssh, depends on com.jcraft:jsch 0.1.55 — the final release of that project — whose
only key types are DSA, ECDSA, RSA and PKCS8; an ed25519 key, or any key stored in the OpenSSH
key file format, is rejected with invalid privatekey before a connection is even attempted.
With scpexe://, key handling follows the local OpenSSH configuration, so ed25519 keys,
ssh-agent and ~/.ssh/config all work. See codelibs/fess-parent#64.

Verification

• project.distributionManagement.snapshotRepository.url resolves to the scpexe:// URL
• mvn validate does not log Installing Central Publishing features, i.e. the Central
  Publishing lifecycle participant stays inactive and maven-deploy-plugin keeps its
  default-deploy execution
• mvn deploy runs maven-deploy-plugin:3.1.4:deploy and hands the transfer to the platform
  SSH client, so the transport resolves and key handling is out of the way. The transfer itself
  was not completed, because the verification environment has no route to the repository host.

Depends on

• fix(build): repair the deployment setup added in #61 fess-parent#62
• fix(build): use wagon-ssh-external so modern SSH keys work fess-parent#64 — must be merged first, otherwise deployment fails with
  Unsupported transport protocol scpexe

Note for whoever runs the deployment

settings.xml needs codelibs-repo / codelibs-snapshots server entries.