refactor(config): migrate to SDKConfig and streamline proxy handling

- Replaced `config.Config` with `config.SDKConfig` across components for simpler configuration management.
- Updated proxy setup functions and handlers to align with `SDKConfig` improvements.
- Reorganized handler imports to match new SDK structure.

sdk/config/config.go

@@ -0,0 +1,14 @@
+// Package config provides configuration management for the CLI Proxy API server.
+// It handles loading and parsing YAML configuration files, and provides structured
+// access to application settings including server port, authentication directory,
+// debug settings, proxy configuration, and API keys.
+package config
+
+// SDKConfig represents the application's configuration, loaded from a YAML file.
+type SDKConfig struct {
+	// ProxyURL is the URL of an optional proxy server to use for outbound requests.
+	ProxyURL string `yaml:"proxy-url" json:"proxy-url"`
+
+	// RequestLog enables or disables detailed request logging functionality.
+	RequestLog bool `yaml:"request-log" json:"request-log"`
+}