feat(AIML-644): add org-level contrast_api methods

- get_org_open_remediations: POST /organizations/{orgId}/remediations/open
  with appIds in body; best-effort, returns [] on error
- get_org_remediation_details: POST /organizations/{orgId}/remediation-details
  with appIds; returns dict with applicationId and skippedAppIds
- get_org_prompt_details: POST /organizations/{orgId}/prompt-details
  with appIds; handles 503 (all apps inaccessible) gracefully
- notify_remediation_pr_opened/closed/merged/failed_org: org-level PUT
  lifecycle endpoints dropping /applications/{appId}/ from URL
- send_telemetry_data_org: org-level POST telemetry endpoint

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: JacobMagesHaskinsContrast