maint/build ~ add dev helper scripts to derive available utils for feature set

util/show-utils.BAT

@@ -0,0 +1,24 @@
+@setLocal
+@echo off
+
+@rem ::# spell-checker:ignore (CMD) ERRORLEVEL
+@rem ::# spell-checker:ignore (utils) cksum dircolors hashsum mkdir mktemp printenv printf readlink realpath relpath rmdir shuf tsort unexpand uutils
+@rem ::# spell-checker:ignore (jq) deps startswith
+
+@rem refs: <https://forge.rust-lang.org/release/platform-support.html> , <https://docs.rs/platforms/0.2.1/platforms/platform/tier1/index.html>
+
+@rem :: default ("Tier 1" cross-platform) utility list
+set "default_utils=base32 base64 basename cat cksum comm cp cut date dircolors dirname echo env expand expr factor false fmt fold hashsum head join link ln ls mkdir mktemp more mv nl od paste printenv printf ptx pwd readlink realpath relpath rm rmdir seq shred shuf sleep sort split sum tac tail tee test tr true truncate tsort unexpand uniq wc yes"
+
+@:: `jq` available?
+set "JQ="
+set "ERRORLEVEL="
+jq --version 1>NUL 2>&1
+if NOT ERRORLEVEL 1 ( set "JQ=jq" )
+
+if NOT DEFINED JQ (
+    echo WARN: missing `jq` ^(install with `scoop install jq`^)^; falling back to default ^(only fully cross-platform^) util list 1>&2
+    echo %default_utils%
+) else (
+    cargo metadata %* --format-version 1 | jq -r "[.resolve.nodes[] | {id: .id, deps: [.deps[].name]}] | .[] | select(.id|startswith(\"uutils\")) | [.deps[] | select(startswith(\"uu_\"))] | [.[] | sub(\"^uu_\"; \"\")] | join(\" \")"
+)