Add F4MouseCursor.png and F4MouseCursor.svg assets and wire up a CSS variable (--co-cursor) to use the custom cursor in the browser. Update styles.css to apply the cursor variable to body and interactive elements. Modify deploy-all.bat to create %PRISMA_ROOT%\misc and copy the PNG to %PRISMA_ROOT%\misc\cursor.png at deploy time, with a warning if the file is missing. This enables a consistent custom cursor for the PrismaUI_F4 runtime (runtime reads misc\cursor.png) while still providing a browser CSS fallback.
