feat: initial commit - Go + CGO captcha recognition service

Features:
- Go + CGO ONNX/OpenCV wrapper for high performance
- SQLite (default) / MySQL database support
- Optional Redis caching
- JWT authentication system
- Multiple captcha recognition APIs:
  - OCR text recognition
  - Slider captcha matching
  - Image similarity comparison
  - Rotation captcha detection
  - Object detection
- React frontend with install wizard
- Docker and docker-compose support
- Gitea CI/CD pipeline

Project structure:
- cmd/server: Main entry point
- internal/: Core business logic
- pkg/onnx: ONNX Runtime CGO wrapper
- pkg/opencv: OpenCV CGO wrapper
- web/: React frontend
- deploy/: Deployment configs
- scripts/: Utility scripts

web/src/index.css

@@ -0,0 +1,160 @@
+* {
+  margin: 0;
+  padding: 0;
+  box-sizing: border-box;
+}
+
+:root {
+  --primary: #3b82f6;
+  --primary-dark: #2563eb;
+  --bg-primary: #0f172a;
+  --bg-secondary: #1e293b;
+  --bg-tertiary: #334155;
+  --text-primary: #f1f5f9;
+  --text-secondary: #94a3b8;
+  --text-muted: #64748b;
+  --border: #334155;
+  --border-hover: #475569;
+  --error: #ef4444;
+  --success: #22c55e;
+}
+
+body {
+  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
+  background: var(--bg-primary);
+  color: var(--text-primary);
+  min-height: 100vh;
+}
+
+.container {
+  max-width: 1200px;
+  margin: 0 auto;
+  padding: 24px;
+}
+
+.card {
+  background: var(--bg-secondary);
+  border: 1px solid var(--border);
+  border-radius: 8px;
+  padding: 24px;
+  margin-bottom: 16px;
+}
+
+.input {
+  width: 100%;
+  padding: 12px 16px;
+  background: var(--bg-tertiary);
+  border: 1px solid var(--border);
+  border-radius: 6px;
+  color: var(--text-primary);
+  font-size: 14px;
+  outline: none;
+  transition: border-color 0.2s;
+}
+
+.input:focus {
+  border-color: var(--primary);
+}
+
+.button {
+  padding: 10px 20px;
+  background: var(--primary);
+  color: white;
+  border: none;
+  border-radius: 6px;
+  font-size: 14px;
+  font-weight: 500;
+  cursor: pointer;
+  transition: background 0.2s;
+}
+
+.button:hover {
+  background: var(--primary-dark);
+}
+
+.button:disabled {
+  opacity: 0.5;
+  cursor: not-allowed;
+}
+
+.button-secondary {
+  background: var(--bg-tertiary);
+}
+
+.button-secondary:hover {
+  background: var(--border);
+}
+
+.label {
+  display: block;
+  margin-bottom: 8px;
+  font-size: 13px;
+  font-weight: 500;
+  color: var(--text-secondary);
+}
+
+.form-group {
+  margin-bottom: 20px;
+}
+
+.error {
+  color: var(--error);
+  font-size: 13px;
+  margin-top: 8px;
+}
+
+.success {
+  color: var(--success);
+  font-size: 13px;
+  margin-top: 8px;
+}
+
+.text-center {
+  text-align: center;
+}
+
+.flex {
+  display: flex;
+}
+
+.flex-col {
+  flex-direction: column;
+}
+
+.items-center {
+  align-items: center;
+}
+
+.justify-between {
+  justify-content: space-between;
+}
+
+.gap-2 {
+  gap: 8px;
+}
+
+.gap-4 {
+  gap: 16px;
+}
+
+.mt-4 {
+  margin-top: 16px;
+}
+
+.mb-4 {
+  margin-bottom: 16px;
+}
+
+.grid {
+  display: grid;
+}
+
+.grid-cols-2 {
+  grid-template-columns: repeat(2, 1fr);
+}
+
+@media (max-width: 768px) {
+  .grid-cols-2 {
+    grid-template-columns: 1fr;
+  }
+}