fix: round 2 audit fixes, updated emulator profiles

Scripts:
- fix generate_site nav regex destroying mkdocs.yml content
- fix auto_fetch comma-separated MD5 in find_missing
- fix verify print_platform_result conflating untested/missing
- fix validate_pr path traversal and symlink check
- fix batocera_scraper brace counting and escaped quotes in strings
- fix emudeck_scraper hash search crossing function boundaries
- fix pipeline.py cwd to repo root via Path(__file__)
- normalize SHA1 comparison to lowercase in generate_pack

Emulator profiles:
- emux_gb/nes/sms: reclassify from alias to standalone profiles
- ep128emu: remove .info-only files not referenced in source
- fbalpha2012 variants: full source-verified profiles
- fbneo_cps12: add new profile

scripts/generate_site.py

@@ -797,7 +797,7 @@ def main():
     # Replace nav section (everything from \nnav: to the next top-level key or EOF)
     import re
     if "\nnav:" in content:
-        content = re.sub(r'\nnav:.*', '\n' + nav_yaml.rstrip(), content, count=1, flags=re.DOTALL)
+        content = re.sub(r'\nnav:\n(?:[ \t]+.*\n?)*', '\n' + nav_yaml, content, count=1)
     else:
         content += "\n" + nav_yaml
     with open("mkdocs.yml", "w") as f: