Native Microsoft Planner integration for Sleekplan roadmap sync

Description: A native integration that links Sleekplan public roadmap items with Microsoft Planner tasks to enable seamless synchronization between both systems. Purpose: Keep internal planning in Microsoft Planner aligned with the public Sleekplan roadmap without manual duplication, ensuring stakeholders and customers see accurate progress while teams work in Planner. Benefits: Eliminate manual copy/paste and reduce syncing errors. Maintain consistent statuses and timelines across public roadmap and internal tasks. Improve transparency with automatic links between public items and internal tasks. Speed up updates and reduce operational overhead. Provide supported APIs/webhooks for teams that need custom extensions. Key Features: Connect a Sleekplan workspace/roadmap to a selected Microsoft Planner Plan (and optional Buckets). Configurable one-way (Sleekplan → Planner) or two-way sync for titles, descriptions, statuses, labels/tags, and due dates. Status mapping between Sleekplan roadmap stages and Planner progress/buckets. Automatic creation and updates of Planner tasks when public roadmap items are added or changed in Sleekplan, with persistent cross-links. Option to pull back key changes from Planner to Sleekplan (e.g., status, due date) when two-way sync is enabled. Admin UI to configure field mappings, sync direction, filters (e.g., only public items, specific statuses or tags), and sync schedule. Secure Microsoft 365 OAuth 2.0 authentication with least-privilege scopes and role-based access. Robust error handling with logs and retry mechanisms to avoid duplicates. Officially documented API and webhook support to enable custom workflows beyond the default integration.