docs: map existing codebase with PAUL

- stack.md - PrestaShop 1.7.x, PHP, Smarty, SCSS, modules
- architecture.md - MVC + hooks, override mechanism, CQRS in src/
- structure.md - Directory layout, key file locations
- conventions.md - PHP/Smarty/SCSS/JS conventions, PS patterns
- testing.md - No automated tests in custom modules
- integrations.md - Allegro, Empik, BaseLinker, shipping, payments
- concerns.md - Override fragility, EOL risk, missing CI/CD
- db_schema.md - Custom tables, modified core tables

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

.paul/codebase/stack.md

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+# Technology Stack
+
+**Analysis Date:** 2026-04-27
+
+## Languages
+
+**Primary:**
+- PHP 7.x+ - All server-side logic (modules, overrides, controllers)
+- Smarty - Template engine for `.tpl` theme files in `themes/InterBlue/templates/`
+
+**Secondary:**
+- SCSS/CSS - Stylesheets in `themes/InterBlue/assets/css/`
+- JavaScript - Frontend logic in `themes/InterBlue/assets/js/`
+
+## Runtime
+
+**Environment:**
+- PHP 5.6+ minimum requirement (targeting PHP 7.x+ for PS 1.7.x stability)
+- MySQL/MariaDB - Database (`interblue_sklep` on `dedyk75.cyber-folks.pl`)
+- Memcached - Caching layer (`ps_caching: 'CacheMemcached'`)
+
+**Package Manager:**
+- No Node.js package manager for custom code
+- Composer used by individual modules (empikmarketplace, autoupgrade)
+
+## Frameworks
+
+**Core:**
+- PrestaShop 1.7.x - E-commerce framework (MVC + Hooks)
+- Symfony components - Used internally by PS 1.7 (service container, YAML)
+
+**Testing:**
+- None - No test framework in custom modules
+
+**Build/Dev:**
+- VSCode Live Sass Compiler - Compiles `custom.scss` to `custom.css` (compressed + sourcemap)
+- Config: `.vscode/settings.json`
+
+## Key Dependencies
+
+**Critical:**
+- PrestaShop 1.7.x - Core e-commerce platform
+- `prestashop/module-lib-service-container` (^1.4) - PSR-11 container for empikmarketplace
+- `guzzlehttp/guzzle` - HTTP client (analytics, integration modules)
+
+**Marketplace Modules:**
+- x13allegro 7.4.0 - Allegro integration - `modules/x13allegro/`
+- empikmarketplace 2.3.0 - Empik integration - `modules/empikmarketplace/`
+- baselinker 0.0.25 - BaseLinker webservice - `modules/baselinker/`
+
+**Shipping Modules:**
+- dpdpoland 4.5.0 - `modules/dpdpoland/`
+- sensbitinpost 5.9.2 - `modules/sensbitinpost/`
+- sensbitpocztapolska 5.6.2 - `modules/sensbitpocztapolska/`
+
+**Payment Modules:**
+- przelewy24 1.3.96 - `modules/przelewy24/`
+- imoje 1.3.4 - `modules/imoje/`
+
+## Configuration
+
+**Environment:**
+- Database credentials: `app/config/parameters.php`
+- DB host: `dedyk75.cyber-folks.pl`, DB: `interblue_sklep`, prefix: `ps_`
+- Mailer: SMTP (localhost 127.0.0.1)
+- Locale: `pl-PL`
+
+**Build:**
+- `.vscode/settings.json` - Live Sass Compiler config
+- `themes/InterBlue/config/theme.yml` - Theme metadata and hook assignments
+
+## Platform Requirements
+
+**Development:**
+- Windows + VSCode with Live Sass Compiler extension
+- SFTP/FTP Sync extension for deployment
+
+**Production:**
+- Hosting: dedyk75.cyber-folks.pl (cyber-folks.pl)
+- Deployment: Manual FTP via `.vscode/ftp-kr.json`
+- Cache clearing: Manual via admin panel or `var/cache/` deletion
+
+---
+
+*Stack analysis: 2026-04-27*
+*Update after major dependency changes*