refactor: split monolithic main.go into modular structure

Refactored 800+ line main.go into clean, domain-separated files:
- main.go (96 lines) - Entry point and command router only
- types.go - Type definitions and data structures
- client.go - HTTP client and request handling
- cmd_kv.go - Key-value operations (get/put/delete)
- cmd_meta.go - Resource metadata commands
- cmd_user.go - User management commands
- cmd_profile.go - Profile management
- cmd_cluster.go - Cluster operations (members/health)
- cmd_system.go - System commands (connect/auth/help)
- utils.go - Shared utilities (parsing, colors, completion)

No functional changes, pure reorganization for maintainability.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

cmd_kv.go

@@ -0,0 +1,125 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"os"
+	"strings"
+	"time"
+)
+
+func (c *KVSClient) handleGet(args []string) {
+	if len(args) < 1 {
+		fmt.Println(red("Usage: get <key>"))
+		return
+	}
+
+	respBody, status, err := c.doRequest("GET", "/kv/"+args[0], nil)
+	if err != nil {
+		fmt.Println(red("Error:"), err)
+		return
+	}
+
+	if status == 404 {
+		fmt.Println(yellow("Key not found"))
+		return
+	}
+
+	if status != 200 {
+		fmt.Println(red("Error:"), string(respBody))
+		return
+	}
+
+	var stored StoredValue
+	if err := json.Unmarshal(respBody, &stored); err != nil {
+		fmt.Println(red("Error parsing response:"), err)
+		return
+	}
+
+	fmt.Println(cyan("UUID:     "), stored.UUID)
+	fmt.Println(cyan("Timestamp:"), time.UnixMilli(stored.Timestamp).Format(time.RFC3339))
+	fmt.Println(cyan("Data:"))
+
+	var pretty bytes.Buffer
+	json.Indent(&pretty, stored.Data, "", "  ")
+	fmt.Println(pretty.String())
+}
+
+func (c *KVSClient) handlePut(args []string) {
+	if len(args) < 1 {
+		fmt.Println(red("Usage: put <key> <json-data>"))
+		fmt.Println("Or: put <key> (then paste JSON on next line)")
+		return
+	}
+
+	var jsonStr string
+	if len(args) == 1 {
+		// Multiline mode - read from next input
+		fmt.Println(yellow("Enter JSON (Ctrl+D when done):"))
+		scanner := bufio.NewScanner(os.Stdin)
+		var lines []string
+		for scanner.Scan() {
+			lines = append(lines, scanner.Text())
+		}
+		jsonStr = strings.Join(lines, "\n")
+	} else {
+		// Single line mode
+		jsonStr = strings.Join(args[1:], " ")
+	}
+
+	// Parse JSON data
+	var data json.RawMessage
+	if err := json.Unmarshal([]byte(jsonStr), &data); err != nil {
+		printJSONError(jsonStr, err)
+		return
+	}
+
+	respBody, status, err := c.doRequest("PUT", "/kv/"+args[0], data)
+	if err != nil {
+		fmt.Println(red("Error:"), err)
+		return
+	}
+
+	if status != 200 && status != 201 {
+		fmt.Println(red("Error:"), string(respBody))
+		return
+	}
+
+	type PutResponse struct {
+		UUID      string `json:"uuid"`
+		Timestamp int64  `json:"timestamp"`
+	}
+
+	var resp PutResponse
+	if err := json.Unmarshal(respBody, &resp); err == nil {
+		fmt.Println(green("Stored successfully"))
+		fmt.Println(cyan("UUID:     "), resp.UUID)
+		fmt.Println(cyan("Timestamp:"), time.UnixMilli(resp.Timestamp).Format(time.RFC3339))
+	}
+}
+
+func (c *KVSClient) handleDelete(args []string) {
+	if len(args) < 1 {
+		fmt.Println(red("Usage: delete <key>"))
+		return
+	}
+
+	_, status, err := c.doRequest("DELETE", "/kv/"+args[0], nil)
+	if err != nil {
+		fmt.Println(red("Error:"), err)
+		return
+	}
+
+	if status == 404 {
+		fmt.Println(yellow("Key not found"))
+		return
+	}
+
+	if status == 204 {
+		fmt.Println(green("Deleted successfully"))
+	} else {
+		fmt.Println(red("Unexpected status:"), status)
+	}
+}