Fix scale-to-zero with authenticated Coherence health mutators (Bug 40013873)

[vasac]

Coherence health endpoint hardening removed GET mutators and requires explicit enablement and authentication. The Operator’s generated GET /suspend therefore fails, blocking scale-to-zero.

This change:

• Uses PUT /suspend and adds method-aware HTTP actions with Secret-backed Basic authentication and verified TLS.
• Adds opt-in healthMutatorConnection configuration, including Coherence TLS and JAAS setup, a packaged credential validator, and HTTPS health probes.
• Propagates suspension failures through scaling and finalization, blocking scale-to-zero when authentication or TLS verification fails.
• Preserves explicit custom probes and legacy health-server behavior.
• Corrects ReadyAction result reporting and prevents repeated execution while a Pod remains Ready.
• Adds configuration examples, admission coverage, and CI workflows for client, Java support, and runtime acceptance tests.

Recorded runtime qualification with Coherence CE 15.1.1-0-5 demonstrated authentication checks, invalid-trust rejection, scale-to-zero and restart, stable PVC identity, and recovery of 257 persistent entries. CE 22.06.18 passed startup and HTTPS/authentication smoke checks.

[sonarqubecloud]

Quality Gate passed

Issues
24 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud