feat: implement modular lab tool structure with working CLI

- Add lab/ module structure (core, machines, deployment, monitoring)
- Add mcp/ server stub for future MCP integration
- Update main.scm to use new modular architecture
- Fix utils/config.scm to export get-current-config function
- Create comprehensive test suite with all modules passing
- Update TODO.md with completed high priority tasks

Key improvements:
- Modular design following K.I.S.S principles
- Working CLI interface for status, machines, deploy commands
- Infrastructure status checking functional
- All module tests passing
- Clean separation of pure/impure functions

CLI now works: ./main.scm status, ./main.scm machines, ./main.scm deploy <machine>

packages/lab-tool/lab/machines.scm

@@ -0,0 +1,19 @@
+;; lab/machines.scm - Machine management (impure)
+
+(define-module (lab machines)
+  #:use-module (utils config)
+  #:use-module (utils logging)
+  #:export (list-machines
+            get-machine-info))
+
+;; Impure function: List all machines with logging
+(define (list-machines)
+  "List all configured machines (impure - has logging side effects)"
+  (log-debug "Listing machines...")
+  (get-all-machines))
+
+;; Impure function: Get machine information
+(define (get-machine-info machine-name)
+  "Get detailed machine information (impure - has logging side effects)"
+  (log-debug "Getting info for machine: ~a" machine-name)
+  (get-machine-config machine-name))