docs: add MariaDB user permissions reference to bible-local

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

bible-local/03-database.md

@@ -360,6 +360,39 @@ Retained for historical data only. Not queried by QuoteForge.
 **machine**: machine_name (PK, char 255), machine_description
 **machine_log**: machine_log_id AUTO_INCREMENT, date, supplier (FK→supplier), country, opty, type, machine (FK→machine), customer_requirement, variant, price_gpl, price_estimate, qty, quality, carepack, lead_time_weeks, prepayment_percent, price_got, Comment
 
+## MariaDB User Permissions
+
+The application user needs read-only access to reference tables and read/write access to runtime tables.
+
+```sql
+-- Read-only: reference and pricing data
+GRANT SELECT ON RFQ_LOG.qt_categories            TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.qt_lot_metadata          TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.qt_pricelists            TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.qt_pricelist_items       TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.stock_log                TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.stock_ignore_rules       TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.qt_partnumber_books      TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.qt_partnumber_book_items TO 'qfs_user'@'%';
+GRANT SELECT ON RFQ_LOG.lot                      TO 'qfs_user'@'%';
+
+-- Read/write: runtime sync and user data
+GRANT SELECT, INSERT, UPDATE, DELETE ON RFQ_LOG.qt_projects              TO 'qfs_user'@'%';
+GRANT SELECT, INSERT, UPDATE, DELETE ON RFQ_LOG.qt_configurations        TO 'qfs_user'@'%';
+GRANT SELECT, INSERT, UPDATE         ON RFQ_LOG.qt_client_schema_state   TO 'qfs_user'@'%';
+GRANT SELECT, INSERT, UPDATE         ON RFQ_LOG.qt_pricelist_sync_status TO 'qfs_user'@'%';
+GRANT SELECT, INSERT, UPDATE         ON RFQ_LOG.qt_vendor_partnumber_seen TO 'qfs_user'@'%';
+
+FLUSH PRIVILEGES;
+```
+
+Rules:
+- `qt_client_schema_state` requires INSERT + UPDATE for sync status tracking (uses `ON DUPLICATE KEY UPDATE`);
+- `qt_vendor_partnumber_seen` requires INSERT + UPDATE (vendor PN discovery during sync);
+- no DELETE is needed on sync/tracking tables — rows are never removed by the client;
+- `lot` SELECT is required for the connection validation probe in `/setup`;
+- the setup page shows `can_write: true` only when `qt_client_schema_state` INSERT succeeds.
+
 ## Migrations
 
 SQLite: