Fix CLI path references in Python code

All Python scripts now use correct cli/ prefix in:
- Usage docstrings (shown in --help)
- Print statements (shown to users)
- Subprocess calls (when calling other scripts)

Changes:
- cli/doc_scraper.py: Fixed 9 references (usage, print, subprocess)
- cli/enhance_skill_local.py: Fixed 6 references (usage, print)
- cli/enhance_skill.py: Fixed 5 references (usage, print)
- cli/package_skill.py: Fixed 4 references (usage, epilog)
- cli/estimate_pages.py: Fixed 3 references (epilog examples)

All commands now correctly show:
- python3 cli/doc_scraper.py (not python3 doc_scraper.py)
- python3 cli/enhance_skill.py (not python3 enhance_skill.py)
- python3 cli/enhance_skill_local.py (not python3 enhance_skill_local.py)
- python3 cli/package_skill.py (not python3 package_skill.py)
- python3 cli/estimate_pages.py (not python3 estimate_pages.py)

Also fixed:
- Old hardcoded path in enhance_skill_local.py:221
  (was: /mnt/skills/examples/skill-creator/scripts/package_skill.py)
  (now: cli/package_skill.py)
- Old hardcoded path in enhance_skill.py:210
  (was: /mnt/skills/examples/skill-creator/scripts/package_skill.py)
  (now: cli/package_skill.py)

This ensures all user-facing messages and subprocess calls use the
correct paths when run from the repository root.

Related: PR #145

cli/estimate_pages.py

@@ -215,13 +215,13 @@ def main():
         epilog="""
 Examples:
   # Estimate pages for a config
-  python3 estimate_pages.py configs/react.json
+  python3 cli/estimate_pages.py configs/react.json
 
   # Estimate with higher discovery limit
-  python3 estimate_pages.py configs/godot.json --max-discovery 2000
+  python3 cli/estimate_pages.py configs/godot.json --max-discovery 2000
 
   # Quick estimate (stop at 100 pages)
-  python3 estimate_pages.py configs/vue.json --max-discovery 100
+  python3 cli/estimate_pages.py configs/vue.json --max-discovery 100
         """
     )