feat(metadata): normalize and synchronize SQL metadata headers

[MayerTim]

Summary

Adds broader metadata-header support for Watcom SQL files.

This branch improves how SQLovely detects, normalizes, updates, and documents metadata headers across procedures, functions, triggers, and multi-object SQL scripts.

Changes

• Normalize loose legacy metadata headers into the current SQLovely metadata format
• Support older metadata labels such as geändert von, geupdated von, and geupdated am
• Add the new Updated By metadata field below Author
• Normalize metadata dates to YYYY-MM-DD
• Support multiline Description values
• Automatically wrap long descriptions to the configured max line length
• Preserve manual line breaks inside descriptions during formatting
• Synchronize Version with the latest history entry
• Add missing history entries when the metadata version is bumped
• Correct invalid version jumps to the next valid increment
• Process all supported SQL objects in multi-object scripts instead of only the first object
• Improve metadata syntax highlighting and TextMate scopes
• Add regression coverage for legacy headers, version/history synchronization, multiline descriptions, date normalization, and multi-object scripts
• Update README, changelog, implementation docs, development notes, contribution docs, and packaging checklist

Testing

• Ran the full test suite successfully
• Current result: All SQLovely tests passed (77 assertions)