Update wiki source files (the single source of truth for the site):
- tools.md: renumber pipeline steps 1-8, add step 6 (pack integrity),
add missing CLI flags for cross_reference.py and refresh_data_dirs.py
- architecture.md: update mermaid diagram with pack integrity step,
fix test file count (5 files, 249 tests)
- testing-guide.md: add test_pack_integrity section, add step 5 to
verification discipline checklist
9 new wiki pages: getting-started, faq, troubleshooting,
advanced-usage, verification-modes, adding-a-platform,
adding-a-scraper, testing-guide, release-process.
Updated architecture.md with mermaid diagrams, tools.md with
full pipeline and target/exporter sections, profiling.md with
missing fields, index.md with glossary and nav links.
Expanded CONTRIBUTING.md from stub to full contributor guide.
Filter .old.yml from load_emulator_profiles, generate_db alias
collection, and generate_readme counts. Fix BizHawk sha1 mode
in tools.md, fix RetroPie path, fix export_truth.py typos.
