Add key features and description

List key features of the library. Add a short
package description.

Fix dotnet#92228

src/libraries/Microsoft.Extensions.Logging.TraceSource/src/PACKAGE.md

@@ -2,20 +2,50 @@
 
 <!-- A description of the package and where one can find more documentation -->
 
-
+Implements a trace logger provider for the .NET logging infrastructre facilitating enhanced logging capabilities and trace-level diagnostics in application by writing messages to a trace listener using System.Diagnostic.TraceSource.
 
 ## Key Features
 
 <!-- The key features of this package -->
 
-*
-*
-*
+* Seamless integration with .NET logging infrastructure.
+* Fine-grained control over trace messages using SourceSwitch.
+* A set of builder methods to configure logging infrastructure.
 
 ## How to Use
 
 <!-- A compelling example on how to use this package with code, as well as any specific guidelines for when to use the package -->
 
+The Microsoft.Extensions.Logging.TraceSource library provides extension methods to the logger factory and the logger builder to add a trace source with trace listeners.
+
+```csharp
+using System.Diagnostics;
+using Microsoft.Extensions.Logging;
+
+using var consoleTraceListener = new ConsoleTraceListener();
+using var textWriterTraceListener = new TextWriterTraceListener("/traces.txt");
+using var loggerFactory = LoggerFactory.Create(builder =>
+{
+    builder
+        .AddTraceSource(new SourceSwitch("Something") { Level = SourceLevels.All }, consoleTraceListener)
+        .AddTraceSource(new SourceSwitch("HouseKeeping") { Level = SourceLevels.All }, textWriterTraceListener);
+});
+
+var logger = loggerFactory.CreateLogger<Program>();
+
+logger.LogInformation("Information message.");
+// Program Information: 0 : Information message.
+logger.LogWarning("Warning message.");
+// Program Warning: 0 : Warning message.
+
+var traceSource = new TraceSource("HouseKeeping", SourceLevels.All);
+traceSource.Listeners.Add(consoleTraceListener);
+traceSource.Listeners.Add(textWriterTraceListener);
+
+traceSource.TraceEvent(TraceEventType.Error, 0, "Error message.");
+//HouseKeeping Error: 0 : Error message.
+```
+
 ## Main Types
 
 <!-- The main types provided in this library -->