Add quick start guide and implementation summary

Co-authored-by: leogenius360 <87181162+leogenius360@users.noreply.github.com>

Author: Copilot

QUICK_START.md

@@ -0,0 +1,352 @@
+# Quick Start Guide
+
+Get started with the GeniusTechSpace protobuf schemas in 5 minutes!
+
+## 1. Installation
+
+### Install Buf CLI
+
+**macOS**:
+```bash
+brew install bufbuild/buf/buf
+```
+
+**Linux**:
+```bash
+curl -sSL https://github.com/bufbuild/buf/releases/download/v1.47.2/buf-Linux-x86_64 -o /usr/local/bin/buf
+chmod +x /usr/local/bin/buf
+```
+
+**Windows** (Chocolatey):
+```bash
+choco install buf
+```
+
+### Clone Repository
+
+```bash
+git clone https://github.com/geniustechspace/protobuf.git
+cd protobuf
+```
+
+## 2. Validate Schemas
+
+```bash
+# Lint all schemas
+buf lint
+
+# Check formatting
+buf format --diff
+
+# Apply formatting
+buf format -w
+```
+
+## 3. Generate Code
+
+### Generate All Languages
+
+```bash
+buf generate
+```
+
+This generates code in `gen/` directory:
+```
+gen/
+├── go/          # Go packages
+├── python/      # Python modules
+├── java/        # Java classes
+├── typescript/  # TypeScript/JavaScript
+├── csharp/      # C# classes
+└── docs/        # Documentation
+```
+
+### Generate Specific Domain
+
+```bash
+# Generate only users domain
+buf generate --path proto/users/v1/
+
+# Generate only auth domain
+buf generate --path proto/auth/v1/
+```
+
+## 4. Use Generated Code
+
+### Go Example
+
+```go
+package main
+
+import (
+    "context"
+    "log"
+    
+    "google.golang.org/grpc"
+    usersv1 "github.com/geniustechspace/protobuf/gen/go/users/v1"
+)
+
+func main() {
+    conn, _ := grpc.Dial("localhost:9090", grpc.WithInsecure())
+    defer conn.Close()
+    
+    client := usersv1.NewUserServiceClient(conn)
+    
+    resp, err := client.CreateUser(context.Background(), &usersv1.CreateUserRequest{
+        TenantId:  "tenant_123",
+        Email:     "user@example.com",
+        Username:  "johndoe",
+        FirstName: "John",
+        LastName:  "Doe",
+    })
+    
+    if err != nil {
+        log.Fatal(err)
+    }
+    
+    log.Printf("Created user: %s", resp.User.Metadata.Id)
+}
+```
+
+### Python Example
+
+```python
+import grpc
+from gen.python.users.v1 import users_pb2, users_pb2_grpc
+
+channel = grpc.insecure_channel('localhost:9090')
+client = users_pb2_grpc.UserServiceStub(channel)
+
+response = client.CreateUser(users_pb2.CreateUserRequest(
+    tenant_id='tenant_123',
+    email='user@example.com',
+    username='johndoe',
+    first_name='John',
+    last_name='Doe'
+))
+
+print(f"Created user: {response.user.metadata.id}")
+```
+
+### TypeScript Example
+
+```typescript
+import { createPromiseClient } from "@connectrpc/connect";
+import { createGrpcTransport } from "@connectrpc/connect-node";
+import { UserService } from "./gen/typescript/users/v1/users_connect";
+
+const transport = createGrpcTransport({
+  baseUrl: "http://localhost:9090",
+});
+
+const client = createPromiseClient(UserService, transport);
+
+const response = await client.createUser({
+  tenantId: "tenant_123",
+  email: "user@example.com",
+  username: "johndoe",
+  firstName: "John",
+  lastName: "Doe",
+});
+
+console.log(`Created user: ${response.user?.metadata?.id}`);
+```
+
+## 5. Explore Domains
+
+### Core Domain
+Common types, tenant context, events
+```bash
+cat proto/core/README.md
+```
+
+### Auth Domain
+Authentication, sessions, tokens
+```bash
+cat proto/auth/README.md
+```
+
+### Users Domain
+User management, profiles
+```bash
+ls proto/users/v1/
+```
+
+### Tenants Domain
+Multi-tenant management
+```bash
+cat proto/tenants/README.md
+```
+
+### Billing Domain
+Subscriptions, invoices, payments
+```bash
+ls proto/billing/v1/
+```
+
+### Access Policy Domain
+Roles, permissions, authorization
+```bash
+ls proto/access_policy/v1/
+```
+
+### Notifications Domain
+Multi-channel notifications
+```bash
+ls proto/notifications/v1/
+```
+
+## 6. Make Changes
+
+### Create Feature Branch
+
+```bash
+git checkout -b feature/my-changes
+```
+
+### Edit Proto Files
+
+```bash
+# Edit a domain
+vim proto/users/v1/users.proto
+
+# Lint changes
+buf lint
+
+# Format changes
+buf format -w
+```
+
+### Check Breaking Changes
+
+```bash
+buf breaking --against '.git#branch=main'
+```
+
+### Test Generation
+
+```bash
+buf generate
+```
+
+### Commit Changes
+
+```bash
+git add .
+git commit -m "feat: add new field to User"
+git push origin feature/my-changes
+```
+
+## 7. Common Tasks
+
+### List All Services
+
+```bash
+find proto -name "*.proto" -exec grep "^service" {} +
+```
+
+### List All Messages
+
+```bash
+find proto -name "*.proto" -exec grep "^message" {} +
+```
+
+### Count Proto Files
+
+```bash
+find proto -name "*.proto" | wc -l
+```
+
+### View Domain Structure
+
+```bash
+tree proto/
+```
+
+## 8. CI/CD
+
+The repository includes GitHub Actions workflow that:
+- ✅ Lints all changes
+- ✅ Checks for breaking changes
+- ✅ Generates code for all languages
+- ✅ Creates schema inventory
+- ✅ Publishes to Buf Schema Registry (when configured)
+- ✅ Generates per-domain clients
+
+Workflow runs on:
+- Every push
+- Every pull request
+
+## 9. Documentation
+
+### Main Documentation
+- [README.md](README.md) - Overview and features
+- [ARCHITECTURE.md](docs/ARCHITECTURE.md) - Design patterns
+- [CLIENT_GENERATION.md](docs/CLIENT_GENERATION.md) - Generate clients
+- [DEPLOYMENT.md](docs/DEPLOYMENT.md) - Deploy services
+- [CONTRIBUTING.md](CONTRIBUTING.md) - Contribution guide
+
+### Domain Documentation
+- [Core](proto/core/README.md)
+- [Auth](proto/auth/README.md)
+- [Tenants](proto/tenants/README.md)
+
+## 10. Support
+
+### Issues
+Open an issue: https://github.com/geniustechspace/protobuf/issues
+
+### Questions
+Start a discussion: https://github.com/geniustechspace/protobuf/discussions
+
+### Community
+Join Discord: [link]
+
+## Quick Reference
+
+### Buf Commands
+
+```bash
+buf lint                    # Lint schemas
+buf format -w              # Format schemas
+buf breaking               # Check breaking changes
+buf generate               # Generate code
+buf dep update            # Update dependencies
+```
+
+### Directory Structure
+
+```
+protobuf/
+├── proto/                 # Protocol buffer definitions
+│   ├── core/             # Common types
+│   ├── auth/             # Authentication
+│   ├── users/            # User management
+│   ├── access_policy/    # Authorization
+│   ├── tenants/          # Multi-tenancy
+│   ├── billing/          # Payments
+│   └── notifications/    # Notifications
+├── gen/                  # Generated code (gitignored)
+├── docs/                 # Documentation
+├── buf.yaml              # Buf configuration
+├── buf.gen.yaml          # Code generation config
+└── .github/workflows/    # CI/CD pipelines
+```
+
+### Key Concepts
+
+- **Multi-Tenancy**: All requests include `tenant_id`
+- **Versioning**: v1, v2, etc. for backward compatibility
+- **Events**: Domain events for state changes
+- **Metadata**: All entities include common metadata
+- **Pagination**: Standard pagination for lists
+
+## Next Steps
+
+1. ✅ Install Buf and clone repo
+2. ✅ Generate code for your language
+3. ✅ Read domain documentation
+4. ✅ Build your first service
+5. ✅ Contribute improvements
+
+Happy coding! 🚀