Add full CAT support (serial + TCP)

New units: CATEngine (Kenwood + Thetis ZZ* commands), CATSerial
(up to 4 serial ports), CATTcp (multi-client TCP server on port 4992).
MainForm wired with TCATContext callbacks reusing existing WebOn* handlers.
SettingsForm gets a new CAT tab with 4 serial port groups and TCP section.
Settings.pas extended with CAT config fields (per-device, JSON-persisted).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

ewsdr.lpi

@@ -139,6 +139,18 @@
         <Filename Value="Settings.pas"/>
         <IsPartOfProject Value="True"/>
       </Unit>
+      <Unit>
+        <Filename Value="CATEngine.pas"/>
+        <IsPartOfProject Value="True"/>
+      </Unit>
+      <Unit>
+        <Filename Value="CATSerial.pas"/>
+        <IsPartOfProject Value="True"/>
+      </Unit>
+      <Unit>
+        <Filename Value="CATTcp.pas"/>
+        <IsPartOfProject Value="True"/>
+      </Unit>
     </Units>
   </ProjectOptions>
   <CompilerOptions>