Add bind-tools option to ease the server/tools package split

--- meson_options.txt.orig	2025-10-18 09:48:52 UTC
+++ meson_options.txt
@@ -197,6 +197,8 @@ option(
     description: 'enable the memory leak detection in external libraries (libxml2, libuv, OpenSSL)',
 )
 
+option('bind-tools', type: 'feature', value: 'disabled', description: 'build tools only')
+
 option(
     'named-lto',
     type: 'combo',