Add Literate theme showcase image to README

  - Add visual example section after Quick Start
  - Demonstrates colorized output with ANSI 256-color theme

Author: willibrandon

README.md

@@ -81,6 +81,10 @@ func NewLibraryLogger() (*mtlog.Logger, error) {
 }
 ```
 
+## Visual Example
+
+![mtlog with Literate theme](assets/literate-theme.png)
+
 ## Message Templates
 
 mtlog uses message templates that preserve structure throughout the logging pipeline:

assets/literate-theme.png

@@ -0,0 +1,77 @@
+package main
+
+import (
+	"github.com/willibrandon/mtlog"
+	"github.com/willibrandon/mtlog/core"
+	"github.com/willibrandon/mtlog/sinks"
+)
+
+func main() {
+	// Create console sink with template and Literate theme
+	consoleSink, err := sinks.NewConsoleSinkWithTemplateAndTheme(
+		"[{Timestamp:HH:mm:ss} {Level:u3}] {SourceContext}: {Message:lj}",
+		sinks.LiterateTheme(),
+	)
+	if err != nil {
+		panic(err)
+	}
+	
+	logger := mtlog.New(
+		mtlog.WithSink(consoleSink),
+		mtlog.WithAutoSourceContext(),
+		mtlog.WithMinimumLevel(core.DebugLevel),
+	)
+	defer logger.Close()
+
+	// Service startup
+	logger.Information("🚀 Application started successfully on port {Port:000}", 8080)
+	logger.Debug("Configuration loaded from {ConfigFile}", "config/app.yaml")
+	
+	// User authentication
+	logger.Information("User {Username} logged in with role {Role}", "alice", "admin")
+	
+	// API request logging
+	logger.Information("HTTP {Method} {Path} responded {StatusCode:000} in {Duration:F2}ms", 
+		"GET", "/api/v1/products", 200, 45.3)
+	
+	// Business operations
+	logger.Information("Processing order {OrderId} for user {UserId} with total ${Total:F2}", 
+		"ORD-2025-789", 12345, 299.99)
+	
+	// Warning scenarios
+	logger.Warning("Inventory low for product {ProductId}, only {Remaining} items left", 
+		"SKU-1234", 5)
+	
+	// Performance monitoring
+	logger.Information("Database query completed in {QueryTime:F3}ms for {RowCount} rows", 
+		123.456, 1500)
+	
+	// Cache operations
+	logger.Debug("Cache hit for key {CacheKey} with TTL {TTL}s remaining", 
+		"product:popular:today", 3600)
+	logger.Warning("Cache miss for key {CacheKey}, fetching from database", 
+		"user:preferences:12345")
+	
+	// Error scenarios
+	logger.Error("Failed to connect to payment gateway {Gateway}: connection timeout after {Timeout}s", 
+		"stripe", 30)
+	
+	// System metrics with percentage formatting
+	logger.Information("System health: CPU={CpuUsage:P1}, Memory={MemoryUsage:P0}, Disk={DiskUsage:P1}", 
+		0.653, 0.89, 0.421)
+	
+	// Status monitoring
+	logger.Information("Health check passed: Database={DbStatus}, Cache={CacheStatus}, Queue={QueueStatus}",
+		"healthy", "healthy", "degraded")
+	
+	// Batch processing with zero-padding
+	logger.Information("Batch job completed: Processed={Processed:000}, Failed={Failed:000}, Duration={Duration:F1}s",
+		42, 3, 12.7)
+	
+	// Request rate metrics
+	logger.Information("API metrics: {RequestsPerSecond:F1} req/s, {AverageLatency:F0}ms, {ErrorRate:P2}",
+		125.3, 45.2, 0.0234)
+	
+	// Shutdown
+	logger.Information("🛑 Graceful shutdown completed in {Duration:F2}s", 2.34)
+}