CI: show curl tool and libcurl sizes

To see how they change throughout code and/or build changes.

Also:
- improve `file` output.
- tidy-ups.

Closes #20355

appveyor.sh

@@ -115,7 +115,9 @@ elif [ "${BUILD_SYSTEM}" = 'VisualStudioSolution' ]; then
   curl="build/${platdir}/${VC_VERSION}/${PRJ_CFG}/curl${binsuffix}.exe"
 fi
 
-find . \( -name '*.exe' -o -name '*.dll' -o -name '*.lib' -o -name '*.pdb' \) -exec file -- '{}' \;
+find . \( -name '*.exe' -o -name '*.dll' -o -name '*.lib' -o -name '*.pdb' \) -print0 | grep -z curl | xargs -0 file --
+find . \( -name '*.exe' -o -name '*.dll' -o -name '*.lib' -o -name '*.pdb' \) -print0 | grep -z curl | xargs -0 stat -c '%10s bytes: %n' --
+
 if [ -z "${SKIP_RUN:-}" ]; then
   "${curl}" --disable --version
 else