Extend variable pattern matching to support both `#` and `@` markers,
with `@` specifically used for agent context variables. Update regex
patterns, text processing logic, and add sub-graph persistence for agent
variable handling.
- Updated `checkMakeGroupAvailability` to include a check for existing group nodes, preventing group creation if a group node is already selected.
- Modified `useMakeGroupAvailability` and `useNodesInteractions` hooks to incorporate the new group node check, ensuring accurate group creation logic.
- Adjusted UI rendering logic in the workflow panel to conditionally display elements based on node type, specifically for group nodes.
- Enhanced `useNodesInteractions` to better manage group node handlers and connections, ensuring accurate identification of leaf nodes and their branches.
- Updated logic to create handlers based on node connections, differentiating between internal and external connections.
- Refined initial node setup to include target branches for group nodes, improving the overall interaction model for grouped elements.
- Introduced GroupDefault node with metadata and default values for group nodes.
- Enhanced useNodeMetaData hook to handle group node author and description using translations.
- Added translations for group node functionality in English, Japanese, Simplified Chinese, and Traditional Chinese.
- Added `handleUngroup`, `getCanUngroup`, and `getSelectedGroupId` methods to manage ungrouping of selected group nodes.
- Integrated ungrouping logic into the `useShortcuts` hook for keyboard shortcut support (Ctrl + Shift + G).
- Updated UI to include ungroup option in the panel operator popup for group nodes.
- Added translations for the ungroup action in multiple languages.
- Added headNodeIds and leafNodeIds to GroupNodeData to track nodes that receive input and send output outside the group.
- Updated useNodesInteractions hook to include headNodeIds in the group node data.
- Modified isValidConnection logic in useWorkflow to validate connections based on leaf node types for group nodes.
- Enhanced preprocessNodesAndEdges to rebuild temporary edges for group nodes, connecting them to external nodes for visual representation.
