CELDEV-1334 Add current-wiki REST reference ADR

[fpichler]

https://synjira.atlassian.net/browse/CELDEV-1334

Summary

• record canonical local document and space references as the convention for current-wiki REST endpoints
• reject wiki-qualified inputs, including qualifiers naming the current wiki
• require an explicit authorization and disclosure contract for future cross-wiki APIs

Coordinated delivery

Draft 1 of 4 for CELDEV-1334:

1. CELDEV-1334 Add current-wiki REST reference ADR #31
2. CELDEV-1334 Add navigation REST API celements-base#309
3. CELDEV-1334 Manage navigation REST artifact celements-parent-poms#142
4. CELDEV-1334 Deploy navigation REST component celements-web#556

Validation

• documentation reviewed against NAVIGATION_API_PLAN.md
• coordinated local build, REST contract tests, WAR packaging, and runtime smoke checks completed
• manually tested and approved by the requester