Fix import/scoring bugs, split PDF module, modernize admin UI

[JanciP]

Bug fixes:

• Fix Excel import INSERT with 11 placeholders for 10 columns in refresh()
• Remove leftover breakpoint() in getNationalRecordsAida that froze the server
• Fix setRegistration call passing warn as change_type in refresh()
• Fix formatDiveTime computing minutes with % instead of //
• Fix undefined names: 'name' in changeCompName, 'log' in updateStartList, 'lane_df' in dropUnusedColumns, 'self.NR' in getNationalRecordsAida
• Add missing sqlite3 import in compy_data.py
• Fix broken @Property @staticmethod combination on CompyData.version
• Fix storeResults crash on starts without a recorded result
• Remove dead comp_type == "CMAS" branch in computePoints (never matched)
• Fix clubs never importing from Excel ('club' vs 'Club' key check)
• Add missing 'content:' in lane list PDF page counter
• Remove os.chdir side effect in getSavedCompetitions that broke relative database paths
• Sync schemas with code: judge.salt, competition.publish_results, competition_athlete.eligible_national, break.block (--init_db now produces a working database)

Refactoring:

• Extract PDF generation (start/lane/result lists) into compy_pdf.py
• Extract shared constants into compy_constants.py
• Make weasyprint import lazy so the app runs without it (PDF export degrades gracefully, helps macOS setups missing pango)
• Replace system pip-freeze requirements.txt with actual dependencies
• Remove debug print()s and test.html dumps, replace deprecated utcnow

UI:

• Modernize admin page with a light theme matching the judge/results color system (tab bar, cards, striped tables, styled forms)
• Fix invalid font-family "sans" in judge/results stylesheets
• Restyle 404 page

Tooling:

• Add tools/generate_test_data.py: generates an AIDA-style competition Excel file (30 athletes, 3 days, CWT/STA/DYN, results + DNS entries)
• Document test data workflow and admin URL in Readme