Memory Dashboard UI: knowledge browser, tool stats, activity timeline

[kovtcharov]

Summary

Build the frontend Memory Dashboard page for the Agent UI. Provides full visibility into agent memory, tool performance, and temporal items.

Spec: docs/spec/agent-memory-architecture.md → "Observability & Dashboard" → "UI Frontend: Dashboard Views"

Depends on: #574 (Dashboard API)

File: src/gaia/apps/webui/src/pages/MemoryDashboard.tsx

6 Dashboard Sections

1. Header Cards

At-a-glance stats: total memories, sessions, tool calls, success rate. Shows +N today delta.

2. Activity Timeline

GitHub-style contribution graph (30 days). Color-coded: conversations (blue), tool calls (green), knowledge added (purple), errors (red).

3. Knowledge Browser

Main table with filter dropdowns (Context, Category, Entity) + search bar.
Columns: Category, Content, Context, Entity, Confidence, Due, Updated.

• Sensitive items show 🔒 badge, content blurred until clicked
• Entity links clickable to filter
• Inline actions: Edit, Delete, Copy ID, Toggle Sensitive
• "+ Add Memory" button (source='user', confidence=0.8)
• Pagination

4. Tool Performance

Stats table: Tool name, Calls, Success %, Avg Time, Last Error.
Click row to expand full call history.

5. Conversation History Browser

Session list with timestamps, turn counts, first message preview.
Click to view full conversation. FTS5 search bar. Read-only.

6. Upcoming & Overdue (Sidebar)

Time-sensitive items grouped by upcoming vs overdue.

Navigation

Add "Memory" tab to agent UI sidebar alongside Chat/Documents.

Design Principles

• Read-heavy, write-light
• Refresh on page load (no WebSocket needed)
• Pagination everywhere
• All memory user-editable

Acceptance Criteria

• All 6 sections render correctly
• Knowledge browser filters and pagination work
• Sensitive items blurred by default
• Entity links filter the table
• Add/Edit/Delete memory from dashboard
• Activity timeline renders 30-day view
• Tool performance table shows correct stats
• Conversation browser with search
• Upcoming/overdue sidebar shows temporal items
• Memory tab in navigation