docs: introduce bible/ as single source of architectural truth

- Add bible/ with 7 hierarchical English-only files covering overview,
  architecture, database schemas, API endpoints, config/env, backup, and dev guides
- Consolidate all docs from README.md, CLAUDE.md, man/backup.md into bible/
- Simplify CLAUDE.md to a single rule: read and respect the bible
- Simplify README.md to a brief intro with links to bible/
- Remove man/backup.md and pricelists_window.md (content migrated or obsolete)
- Fix API docs: add missing endpoints (preview-article, sync/repair),
  correct DELETE /api/projects/:uuid semantics (variant soft-delete only)
- Add Soft Deletes section to architecture doc (is_active pattern)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

bible/README.md

@@ -0,0 +1,53 @@
+# QuoteForge Bible — Architectural Documentation
+
+The single source of truth for architecture, schemas, and patterns.
+
+---
+
+## Table of Contents
+
+| File | Topic |
+|------|-------|
+| [01-overview.md](01-overview.md) | Product: purpose, features, tech stack, repository structure |
+| [02-architecture.md](02-architecture.md) | Architecture: local-first, sync, pricing, versioning |
+| [03-database.md](03-database.md) | DB schemas: SQLite + MariaDB, permissions, indexes |
+| [04-api.md](04-api.md) | API endpoints and web routes |
+| [05-config.md](05-config.md) | Configuration, environment variables, paths, installation |
+| [06-backup.md](06-backup.md) | Backup: implementation, rotation policy |
+| [07-dev.md](07-dev.md) | Development: commands, code style, guardrails |
+
+---
+
+## Bible Rules
+
+> **Every architectural decision must be recorded in the Bible.**
+>
+> Any change to DB schema, data access patterns, sync behavior, API contracts,
+> configuration format, or any other system-level aspect — the corresponding `bible/` file
+> **must be updated in the same commit** as the code.
+>
+> The Bible is the single source of truth for architecture. Outdated documentation is worse than none.
+
+> **Documentation language: English.**
+>
+> All files in `bible/` are written and updated **in English only**.
+> Mixing languages is not allowed.
+
+---
+
+## Quick Reference
+
+**Where is user data stored?**
+SQLite → `~/Library/Application Support/QuoteForge/qfs.db` (macOS). MariaDB is sync-only.
+
+**How to look up a price for a line item?**
+`local_pricelist_items` → by `pricelist_id` from config + `lot_name`. Prices are **never** taken from `local_components`.
+
+**Pre-commit check?**
+`go build ./cmd/qfs && go vet ./...`
+
+**What must never be restored?**
+cron jobs, admin pricing, alerts, stock import, importer utility — all removed intentionally.
+
+**Where is the release changelog?**
+`releases/memory/v{major}.{minor}.{patch}.md`