feat: use custom app icon for shortcuts and installer

- Generate icon.ico from icon-512.png (16-256px sizes)
- Set MUI_ICON/MUI_UNICON for installer wizard
- Point all shortcuts to icon.ico instead of pythonw.exe
- Add DisplayIcon registry entry for Add/Remove Programs

installer.nsi

@@ -30,6 +30,8 @@ SetCompressor /SOLID lzma
 
 ; ── Modern UI Configuration ─────────────────────────────────
 
+!define MUI_ICON "server\src\wled_controller\static\icons\icon.ico"
+!define MUI_UNICON "server\src\wled_controller\static\icons\icon.ico"
 !define MUI_ABORTWARNING
 
 ; ── Pages ───────────────────────────────────────────────────
@@ -102,7 +104,7 @@ Section "!${APPNAME} (required)" SecCore
   CreateDirectory "$SMPROGRAMS\${APPNAME}"
   CreateShortcut "$SMPROGRAMS\${APPNAME}\${APPNAME}.lnk" \
     "wscript.exe" '"$INSTDIR\scripts\${VBSNAME}"' \
-    "$INSTDIR\python\pythonw.exe" 0
+    "$INSTDIR\app\src\wled_controller\static\icons\icon.ico" 0
   CreateShortcut "$SMPROGRAMS\${APPNAME}\Uninstall.lnk" "$INSTDIR\uninstall.exe"
 
   ; Registry: install location + Add/Remove Programs entry
@@ -117,6 +119,8 @@ Section "!${APPNAME} (required)" SecCore
     "UninstallString" '"$INSTDIR\uninstall.exe"'
   WriteRegStr HKCU "Software\Microsoft\Windows\CurrentVersion\Uninstall\${APPNAME}" \
     "InstallLocation" "$INSTDIR"
+  WriteRegStr HKCU "Software\Microsoft\Windows\CurrentVersion\Uninstall\${APPNAME}" \
+    "DisplayIcon" "$INSTDIR\app\src\wled_controller\static\icons\icon.ico"
   WriteRegStr HKCU "Software\Microsoft\Windows\CurrentVersion\Uninstall\${APPNAME}" \
     "Publisher" "Alexei Dolgolyov"
   WriteRegStr HKCU "Software\Microsoft\Windows\CurrentVersion\Uninstall\${APPNAME}" \
@@ -136,13 +140,13 @@ SectionEnd
 Section "Desktop shortcut" SecDesktop
   CreateShortcut "$DESKTOP\${APPNAME}.lnk" \
     "wscript.exe" '"$INSTDIR\scripts\${VBSNAME}"' \
-    "$INSTDIR\python\pythonw.exe" 0
+    "$INSTDIR\app\src\wled_controller\static\icons\icon.ico" 0
 SectionEnd
 
 Section "Start with Windows" SecAutostart
   CreateShortcut "$SMSTARTUP\${APPNAME}.lnk" \
     "wscript.exe" '"$INSTDIR\scripts\${VBSNAME}"' \
-    "$INSTDIR\python\pythonw.exe" 0
+    "$INSTDIR\app\src\wled_controller\static\icons\icon.ico" 0
 SectionEnd
 
 ; ── Section Descriptions ────────────────────────────────────