feat: Phase 8 - Frontend main views (T-026 to T-031)

Implement all main frontend views for the MITRE ATT&CK coverage platform:

- T-026: Dashboard with coverage summary cards and tactic breakdown table

- T-027: Interactive ATT&CK matrix with filtering by status, tactic, platform

- T-028: Technique detail page with tests, intel items, and review actions

- T-029: Test creation form with technique selector and validation

- T-030: Test detail page with drag and drop evidence upload and download

- T-031: System admin panel with MITRE sync and intel scan controls

New components: CoverageSummaryCard, TacticCoverageChart, AttackMatrix, TechniqueCell, TestForm, EvidenceUpload, EvidenceList

New API modules: metrics.ts, techniques.ts, tests.ts, evidence.ts, system.ts

All views use TanStack Query for data fetching with proper loading and error states. Role-based UI controls for admin/lead actions.

README.md

@@ -18,7 +18,7 @@ Aegis is a comprehensive platform for tracking and managing security coverage ag
 - **Database**: PostgreSQL 15
 - **Object Storage**: MinIO (S3-compatible)
 - **ORM**: SQLAlchemy with Alembic migrations
-- **Frontend**: React 19 + TypeScript + Vite + Tailwind CSS v4
+- **Frontend**: React 19 + TypeScript + Vite + Tailwind CSS v4 + TanStack Query
 
 ## Quick Start
 
@@ -208,19 +208,34 @@ Aegis/
         ├── index.css             # Tailwind CSS entry
         ├── api/                  # Axios clients
         │   ├── client.ts         # Base axios instance with JWT interceptor
-        │   └── auth.ts           # login(), getMe()
+        │   ├── auth.ts           # login(), getMe()
+        │   ├── metrics.ts        # getCoverageSummary(), getCoverageByTactic()
+        │   ├── techniques.ts     # getTechniques(), getTechniqueByMitreId()
+        │   ├── tests.ts          # createTest(), validateTest(), rejectTest()
+        │   ├── evidence.ts       # uploadEvidence(), getEvidence()
+        │   └── system.ts         # triggerMitreSync(), triggerIntelScan()
         ├── context/
         │   └── AuthContext.tsx    # Auth state: user, login, logout, isLoading
         ├── components/
-        │   ├── Layout.tsx        # Sidebar + header + <Outlet/>
-        │   ├── Sidebar.tsx       # Nav links (role-aware)
-        │   └── ProtectedRoute.tsx
+        │   ├── Layout.tsx              # Sidebar + header + <Outlet/>
+        │   ├── Sidebar.tsx             # Nav links (role-aware)
+        │   ├── ProtectedRoute.tsx      # Auth route guard with role support
+        │   ├── CoverageSummaryCard.tsx # Metric card component
+        │   ├── TacticCoverageChart.tsx # Coverage breakdown table
+        │   ├── AttackMatrix.tsx        # Interactive technique grid
+        │   ├── TechniqueCell.tsx       # Individual technique cell in matrix
+        │   ├── TestForm.tsx            # Reusable test creation/edit form
+        │   ├── EvidenceUpload.tsx      # Drag & drop file upload
+        │   └── EvidenceList.tsx        # Evidence file listing
         ├── pages/
-        │   ├── LoginPage.tsx
-        │   ├── DashboardPage.tsx
-        │   ├── TechniquesPage.tsx
-        │   ├── TestsPage.tsx
-        │   └── SystemPage.tsx
+        │   ├── LoginPage.tsx           # User authentication form
+        │   ├── DashboardPage.tsx       # Coverage metrics dashboard with summary cards
+        │   ├── TechniquesPage.tsx      # Interactive ATT&CK matrix view with filters
+        │   ├── TechniqueDetailPage.tsx # Individual technique detail with tests
+        │   ├── TestsPage.tsx           # Tests overview and navigation
+        │   ├── TestCreatePage.tsx      # Test creation form
+        │   ├── TestDetailPage.tsx      # Test details with evidence upload
+        │   └── SystemPage.tsx          # Admin panel for MITRE sync & intel scan
         ├── types/
         │   └── models.ts         # TS interfaces matching backend schemas
         ├── hooks/