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/05-config.md

@@ -0,0 +1,129 @@
+# 05 — Configuration and Environment
+
+## File Paths
+
+### SQLite database (`qfs.db`)
+
+| OS | Default path |
+|----|-------------|
+| macOS | `~/Library/Application Support/QuoteForge/qfs.db` |
+| Linux | `$XDG_STATE_HOME/quoteforge/qfs.db` or `~/.local/state/quoteforge/qfs.db` |
+| Windows | `%LOCALAPPDATA%\QuoteForge\qfs.db` |
+
+Override: `-localdb <path>` or `QFS_DB_PATH`.
+
+### config.yaml
+
+Searched in the same user-state directory as `qfs.db` by default.
+If the file does not exist, it is created automatically.
+If the format is outdated, it is automatically migrated to the runtime format (`server` + `logging` sections only).
+
+Override: `-config <path>` or `QFS_CONFIG_PATH`.
+
+**Important:** `config.yaml` is a runtime user file — it is **not stored in the repository**.
+`config.example.yaml` is the only config template in the repo.
+
+---
+
+## config.yaml Structure
+
+```yaml
+server:
+  host: "0.0.0.0"
+  port: 8080
+  mode: "release"   # release | debug
+
+logging:
+  level: "info"     # debug | info | warn | error
+  format: "json"    # json | text
+  output: "stdout"  # stdout | stderr | /path/to/file
+
+backup:
+  time: "00:00"     # HH:MM in local time
+```
+
+---
+
+## Environment Variables
+
+| Variable | Description | Default |
+|----------|-------------|---------|
+| `QFS_DB_PATH` | Full path to SQLite DB | OS-specific user state dir |
+| `QFS_STATE_DIR` | State directory (if `QFS_DB_PATH` is not set) | OS-specific user state dir |
+| `QFS_CONFIG_PATH` | Full path to `config.yaml` | OS-specific user state dir |
+| `QFS_BACKUP_DIR` | Root directory for rotating backups | `<db dir>/backups` |
+| `QFS_BACKUP_DISABLE` | Disable automatic backups | — |
+| `QF_DB_HOST` | MariaDB host | localhost |
+| `QF_DB_PORT` | MariaDB port | 3306 |
+| `QF_DB_NAME` | Database name | RFQ_LOG |
+| `QF_DB_USER` | DB user | — |
+| `QF_DB_PASSWORD` | DB password | — |
+| `QF_JWT_SECRET` | JWT secret | — |
+| `QF_SERVER_PORT` | HTTP server port | 8080 |
+
+`QFS_BACKUP_DISABLE` accepts: `1`, `true`, `yes`.
+
+---
+
+## CLI Flags
+
+| Flag | Description |
+|------|-------------|
+| `-config <path>` | Path to config.yaml |
+| `-localdb <path>` | Path to SQLite DB |
+| `-reset-localdb` | Reset local DB (destructive!) |
+| `-migrate` | Apply pending migrations and exit |
+| `-version` | Print version and exit |
+
+---
+
+## Installation and First Run
+
+### Requirements
+- Go 1.22 or higher
+- MariaDB 11.x (or MySQL 8.x)
+- ~50 MB disk space
+
+### Steps
+
+```bash
+# 1. Clone the repository
+git clone <repo-url>
+cd quoteforge
+
+# 2. Apply migrations
+go run ./cmd/qfs -migrate
+
+# 3. Start
+go run ./cmd/qfs
+# or
+make run
+```
+
+Application is available at: http://localhost:8080
+
+On first run, `/setup` opens for configuring the MariaDB connection.
+
+### OPS Project Migrator
+
+Migrates quotes whose names start with `OPS-xxxx` (where `x` is a digit) into a project named `OPS-xxxx`.
+
+```bash
+# Preview first (always)
+go run ./cmd/migrate_ops_projects
+
+# Apply
+go run ./cmd/migrate_ops_projects -apply
+
+# Apply without interactive confirmation
+go run ./cmd/migrate_ops_projects -apply -yes
+```
+
+---
+
+## Docker
+
+```bash
+docker build -t quoteforge .
+docker-compose up -d
+```