Atlassian removed GET /rest/api/3/search (HTTP 410, CHANGE-2046), which
broke ticket sync for Jira Cloud customers. Migrate the connector's
search() to POST /rest/api/3/search/jql with cursor pagination
(nextPageToken/isLast) instead of the legacy startAt/total scheme.
Verified end-to-end against a live Jira Cloud instance: TestConnection,
search, FetchUpdated and ListAssignedKeys all succeed and parse issues
correctly. Spec §5.3 updated to document the new endpoint.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>