Add Luna.Configuration with TOML-based agent and provider config

Implement configuration system with embedded TOML resources for agent
and provider definitions, custom IConfigurationSource/Provider for
agent and provider options, and DI extension methods. Includes config
models for agents, providers, sessions, and Telegram integration.

Luna.Configuration/Services/Agents/AgentOptionsConfigurationProvider.cs

@@ -0,0 +1,20 @@
+using System.Reflection;
+using Microsoft.Extensions.Configuration;
+
+namespace Luna.Configuration.Services.Agents;
+
+internal class AgentOptionsConfigurationProvider(IEnumerable<AgentOptions> agentOptions) : ConfigurationProvider
+{
+    public override void Load()
+    {
+        foreach (var options in agentOptions)
+        {
+            var keyPrefix = $"Agents:{options.Name}";
+
+            foreach (var property in options.GetType().GetProperties(BindingFlags.Instance | BindingFlags.Public))
+            {
+                Data[$"{keyPrefix}:{property.Name}"] = property.GetValue(options)?.ToString();
+            }
+        }
+    }
+}