Release v0.1.5: Nested Kanban View

Major Feature: Nested Kanban Board
- Parent tasks now appear in each column where they have subtasks
- Provides hierarchical context while maintaining status-based organization
- Eliminates need to choose between hierarchy and status views

Parent Card Features:
1. Multi-Column Presence
   - Parent card appears in every column containing its descendants
   - Shows "X of Y subtasks in this column" counter
   - Automatically updates as children move between columns

2. Expandable/Collapsible
   - Click chevron to show/hide children in that specific column
   - Each parent instance independently expandable
   - Children displayed nested with indentation

3. Visual Distinction
   - Thicker orange border (border-2 vs border)
   - Bold text styling
   - "bg-cyber-darker" background instead of "bg-cyber-darkest"
   - Non-draggable (only leaf tasks can be moved)

4. Recursive Display
   - getDescendantsInStatus() finds all descendants (not just direct children)
   - Handles arbitrary nesting depth
   - Works with sub-subtasks and beyond

Technical Implementation:
- Added helper functions:
  - getDescendantsInStatus(taskId, allTasks, status)
  - hasDescendantsInStatus(taskId, allTasks, status)
- Modified TaskCard component with isParent and columnStatus props
- Updated KanbanColumn to show both parent and leaf tasks
- Only root-level tasks shown (nested children appear when parent expanded)

Display Logic:
- Each column shows:
  1. Root parent tasks with descendants in that status
  2. Root leaf tasks with that status
- Leaf tasks: tasks with no children
- Parent tasks: tasks with at least one child

Example Usage:
Project "Build Feature"
├─ Backend (2 subtasks in backlog, 1 in progress)
└─ Frontend (1 subtask in done)

Result: Project card appears in 3 columns:
- Backlog: "2 of 3 subtasks in this column"
- In Progress: "1 of 3 subtasks in this column"
- Done: "1 of 3 subtasks in this column"

Documentation:
- Updated README with nested Kanban explanation
- Added v0.1.5 section to CHANGELOG
- Updated version to v0.1.5 in App.jsx
- Moved "Nested Kanban" from roadmap to completed features

This completes the hierarchical task management vision for TESSERACT,
allowing users to see both project structure and status distribution
simultaneously without switching views.

CHANGELOG.md

@@ -5,6 +5,31 @@ All notable changes to TESSERACT will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.1.5] - 2025-01-XX
+
+### Added
+- **Nested Kanban View** - Major feature implementation
+  - Parent tasks now appear in each column where they have subtasks
+  - Parent cards show "X of Y subtasks in this column" indicator
+  - Parent cards are expandable/collapsible to show children in that column
+  - Parent cards have distinct visual styling (thicker orange border, bold text)
+  - Only leaf tasks (tasks with no children) are draggable
+  - Parent cards automatically appear in multiple columns as children move
+- Helper functions for nested Kanban logic:
+  - `getDescendantsInStatus()` - Get all descendant tasks in a specific status
+  - `hasDescendantsInStatus()` - Check if parent has any descendants in a status
+
+### Changed
+- Kanban board now labeled "Kanban Board (Nested View)"
+- Parent task cards cannot be dragged (only leaf tasks)
+- Column task counts now include parent cards
+- Improved visual hierarchy with parent/child distinction
+
+### Improved
+- Better visualization of task distribution across statuses
+- Easier to see project structure while maintaining status-based organization
+- Parent tasks provide context for subtasks in each column
+
 ## [0.1.4] - 2025-01-XX
 
 ### Added