wiki: audit fixes — broken links, wikilinks, frontmatter, stale content (66 files)

- Fixed 4 broken markdown links (bad relative paths in See Also sections)
- Corrected n8n port binding to 127.0.0.1:5678 (matches actual deployment)
- Updated SnapRAID article with actual majorhome paths (/majorRAID, disk1-3)
- Converted 67 Obsidian wikilinks to relative markdown links or plain text
- Added YAML frontmatter to 35 articles missing it entirely
- Completed frontmatter on 8 articles with missing fields

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

01-linux/files-permissions/linux-file-permissions.md

@@ -152,6 +152,6 @@ find /var/www/html -type d -exec chmod 755 {} \;
 
 ## See Also
 
-- [[linux-server-hardening-checklist]]
-- [[ssh-config-key-management]]
-- [[bash-scripting-patterns]]
+- [linux-server-hardening-checklist](../../02-selfhosting/security/linux-server-hardening-checklist.md)
+- [ssh-config-key-management](../networking/ssh-config-key-management.md)
+- [bash-scripting-patterns](../shell-scripting/bash-scripting-patterns.md)