feat: implemented verified Shell Actuator skill

- Enabled execution of whitelisted shell commands via OACP.
- Added neuro-cognitive analysis for command results.
- Fixed authentication fallback for background daemon.
- Finalized Emacs UI robustness for all message types.

notes/org-skill-emacs-bridge.org

@@ -64,7 +64,7 @@ Interfaces for TCP I/O and protocol framing. Source of truth is the OACP specifi
          (msg (prin1-to-string envelope))
          (len (length msg))
          (framed (format nil "~6,'0x~a" len msg)))
-    (write-string (string-downcase framed) stream)
+    (write-string framed stream)
     (finish-output stream)))
 
 (defun broadcast-to-emacs (action-plist context)