jirar 0.0.0.9000

• First release of jirar, a modern client for the Jira REST API supporting both Jira Cloud and Jira Server / Data Center.
• jira_connect() and jira_connection() create connections (reading JIRA_URL, JIRA_USER and JIRA_TOKEN from the environment by default) and pick the right REST API version and authentication scheme per deployment.
• jira_issues() runs a JQL query and returns a tidy tibble, handling token-based pagination on Cloud and offset pagination on Server/Data Center, flattening nested fields, parsing datetimes and extracting plain text from Atlassian Document Format bodies.
• jira_count_issues() returns the number of issues matching a JQL query.
• jira_projects(), jira_fields(), jira_dashboards(), jira_groups(), jira_permissions() and jira_my_permissions() retrieve their respective resources as tibbles.
• jira_server_info() and jira_myself() return instance and current-user metadata.