docs: add Project Overview section to SDD documentation

Document the new SpecStatisticsPanel that appears at the top of the
Task List tab. The section covers the summary line, segmented progress
bar, priority breakdown, checklist progress, archived task count, and
the Hide/Show collapse toggle. Includes the SDD-ProjectOverview.png
screenshot.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: stephanj

docusaurus/docs/features/spec-driven-development.md

@@ -154,6 +154,20 @@ Implement JWT-based authentication for the REST API endpoints.
 
 The **DevoxxGenie Specs** tool window provides two views for managing your task specs: a **Task List** and a **Kanban Board**. Switch between them using the tabs at the top of the tool window.
 
+### Project Overview
+
+The **Project Overview** panel appears at the top of the Task List tab and gives you an instant summary of your backlog health:
+
+![SDD Project Overview](/img/SDD-ProjectOverview.png)
+
+- **Summary line**: shows the total task count, overall completion percentage, and a breakdown by status (e.g. "7 tasks | 14% complete | (1 done, 1 in progress, 5 to do)")
+- **Segmented progress bar**: a color-coded bar visualizing task distribution — green for Done, blue for In Progress, gray for To Do, and yellow for any custom statuses
+- **Priority breakdown**: count of high, medium, and low priority tasks at a glance
+- **Checklist progress**: aggregated acceptance criteria and Definition of Done completion across all tasks (e.g. "12/45 acceptance criteria | 8/20 definition of done")
+- **Archived task count**: displayed when archived tasks exist in the backlog
+
+The panel header has a **Hide/Show** toggle so you can collapse it to save vertical space once you have a feel for your backlog status.
+
 ### Task List
 
 The Task List view displays tasks in a tree structure grouped by status: