Initial MVP implementation of Claudia Docs CLI

- Auth commands: login, logout, status
- Document commands: create, list, get, update, delete
- Project commands: list, get
- Folder commands: list, create
- Tag commands: list, create, add
- Search command
- Reasoning save command
- JSON output format with --output text option
- Viper-based configuration management
- Cobra CLI framework

internal/config/config.go

@@ -0,0 +1,124 @@
+package config
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/spf13/viper"
+)
+
+// Config holds all configuration
+type Config struct {
+	Server  string
+	Token   string
+	Output  string
+	Timeout string
+	Quiet   bool
+	Verbose bool
+}
+
+var cfg *Config
+
+// Load initializes the configuration
+func Load() (*Config, error) {
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return nil, fmt.Errorf("failed to get home directory: %w", err)
+	}
+
+	viper.SetConfigName(".claudia-docs")
+	viper.SetConfigType("yaml")
+	viper.AddConfigPath(home)
+
+	// Set defaults
+	viper.SetDefault("server", "http://localhost:8000")
+	viper.SetDefault("output", "json")
+	viper.SetDefault("timeout", "30s")
+
+	// Environment variables
+	viper.SetEnvPrefix("CLAUDIA")
+	viper.SetEnvKeyReplacer(strings.NewReplacer(".", "_"))
+	viper.AutomaticEnv()
+
+	// Read config file if exists
+	_ = viper.ReadInConfig()
+
+	cfg = &Config{
+		Server:  viper.GetString("server"),
+		Token:   viper.GetString("token"),
+		Output:  viper.GetString("output"),
+		Timeout: viper.GetString("timeout"),
+		Quiet:   viper.GetBool("quiet"),
+		Verbose: viper.GetBool("verbose"),
+	}
+
+	return cfg, nil
+}
+
+// GetToken returns the current token
+func GetToken() string {
+	if cfg == nil {
+		return ""
+	}
+	return cfg.Token
+}
+
+// GetServer returns the current server URL
+func GetServer() string {
+	if cfg == nil {
+		return "http://localhost:8000"
+	}
+	return cfg.Server
+}
+
+// SaveToken saves a token to the config file
+func SaveToken(token string) error {
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return fmt.Errorf("failed to get home directory: %w", err)
+	}
+
+	configPath := filepath.Join(home, ".claudia-docs.yaml")
+	viper.SetConfigFile(configPath)
+
+	viper.Set("token", token)
+
+	return viper.WriteConfig()
+}
+
+// ClearToken removes the token from config
+func ClearToken() error {
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return fmt.Errorf("failed to get home directory: %w", err)
+	}
+
+	configPath := filepath.Join(home, ".claudia-docs.yaml")
+	viper.SetConfigFile(configPath)
+
+	viper.Set("token", "")
+
+	return viper.WriteConfig()
+}
+
+// GetConfig returns the current config
+func GetConfig() *Config {
+	return cfg
+}
+
+// UpdateFromFlags updates config from CLI flags
+func UpdateFromFlags(server, token, output string, quiet, verbose bool) {
+	if server != "" {
+		cfg.Server = server
+	}
+	if token != "" {
+		cfg.Token = token
+	}
+	if output != "" {
+		cfg.Output = output
+	}
+	cfg.Quiet = quiet
+	cfg.Verbose = verbose
+}