fix(b3): eliminate command -v herdr bash function false positive in preflight checks (100% PASS)

.agents/skills/lib.sh

@@ -50,9 +50,51 @@ _HERDR_SKILLS_BIN_PATTERN="${_HERDR_SKILLS_BIN_PATTERN:-/.agents/skills/.bin}"
 
 HERDR_SESSION_NAME="${HERDR_SESSION_NAME:-default}"
 
+_canonical_file() {
+  local p="$1" t d b i=0
+  while [ -L "$p" ] && [ "$i" -lt 40 ]; do
+    t="$(readlink "$p" 2>/dev/null)" || break
+    case "$t" in
+      /*) p="$t" ;;
+      *)  p="$(dirname "$p")/$t" ;;
+    esac
+    i=$((i + 1))
+  done
+  d="$(cd -P "$(dirname "$p")" 2>/dev/null && pwd -P)" || return 1
+  b="$(basename "$p")"
+  printf '%s/%s\n' "$d" "$b"
+}
+
+_is_shim_path() {
+  case "/$1/" in
+    *"/.mam/shim/"*|*-shim/*|*"$_HERDR_SHIM_DIR_PATTERN"*|*"$_HERDR_SKILLS_BIN_PATTERN"/*)
+      return 0 ;;
+  esac
+  return 1
+}
+
 _resolve_real_herdr_path() {
-  _REAL_HERDR_PATH="herdr"
+  local dir cand save_ifs="$IFS" real_path=""
+  IFS=:
+  for dir in $PATH; do
+    [ -n "$dir" ] || continue
+    _is_shim_path "$dir" && continue
+    [ -x "$dir/herdr" ] || continue
+    cand="$(_canonical_file "$dir/herdr" 2>/dev/null)" || cand="$dir/herdr"
+    [ -n "$cand" ] || cand="$dir/herdr"
+    _is_shim_path "$cand" && continue
+    real_path="$dir/herdr"
+    break
+  done
+  IFS="$save_ifs"
+  [ -n "$real_path" ] || return 1
+  _REAL_HERDR_PATH="$real_path"
   export _REAL_HERDR_PATH
+  printf '%s\n' "$real_path"
+}
+
+has_real_herdr() {
+  _resolve_real_herdr_path >/dev/null 2>&1
 }
 
 _init_herdr_isolation() {