fix: installer auto-adds mosaic bin to PATH with clear status output

- install.sh: detects shell profile (zsh/bash/profile), adds PATH entry if missing
- install.ps1: adds to User PATH via SetEnvironmentVariable if missing
- Both are idempotent — show "already in PATH ✓" on re-run
- mosaic/mosaic.ps1: accept "help" and "version" as bare subcommands

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

install.sh

@@ -42,7 +42,31 @@ if ! "$TARGET_DIR/bin/mosaic-doctor"; then
   echo "[mosaic-install] WARNING: doctor reported issues (run ~/.config/mosaic/bin/mosaic-doctor --fail-on-warn)" >&2
 fi
 
-echo "[mosaic-install] Add to PATH: export PATH=\"$TARGET_DIR/bin:$PATH\""
+# Ensure ~/.config/mosaic/bin is in PATH persistently
+PATH_LINE="export PATH=\"$TARGET_DIR/bin:\$PATH\""
+
+# Find the right shell profile
+if [[ -n "${ZSH_VERSION:-}" ]] || [[ "$(basename "${SHELL:-}")" == "zsh" ]]; then
+  SHELL_PROFILE="$HOME/.zshrc"
+elif [[ -f "$HOME/.bashrc" ]]; then
+  SHELL_PROFILE="$HOME/.bashrc"
+elif [[ -f "$HOME/.profile" ]]; then
+  SHELL_PROFILE="$HOME/.profile"
+else
+  SHELL_PROFILE="$HOME/.profile"
+fi
+
+if grep -qF "$TARGET_DIR/bin" "$SHELL_PROFILE" 2>/dev/null; then
+  echo "[mosaic-install] PATH: $TARGET_DIR/bin already in $SHELL_PROFILE ✓"
+else
+  {
+    echo ""
+    echo "# Mosaic agent framework"
+    echo "$PATH_LINE"
+  } >> "$SHELL_PROFILE"
+  echo "[mosaic-install] PATH: Added $TARGET_DIR/bin to $SHELL_PROFILE ✓"
+  echo "[mosaic-install] Run 'source $SHELL_PROFILE' or open a new terminal to activate."
+fi
 
 if [[ ! -f "$TARGET_DIR/SOUL.md" ]]; then
   echo ""