IT: adding auto code review from claude on PR opening

.github/copilot-instructions.md

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+# Copilot Instructions
+
+These instructions apply to code reviews on pull requests in this repository.
+
+## Project Context
+
+This is PayPlug's official Sylius plugin. PayPlug is a Payment Service Provider (PSP). The plugin integrates PayPlug's payment processing into Sylius via multiple payment methods: standard card (PayPlug), Oney financing, Bancontact, Scalapay, Apple Pay, and American Express.
+
+**Stack**: PHP 8.2+, Sylius 2.0+, Symfony 6.4+, Payum, `payplug/payplug-php ^4.0`
+
+## Intentional Patterns — Do Not Flag as Issues
+
+- **`sleep(10)` in `NotifyAction`** — intentional, prevents a race condition between the IPN webhook and the user redirect. Never suggest removing it.
+- **No direct SDK calls** — `PayPlugApiClient` is the only allowed entry point to the PayPlug PHP SDK. Any direct call to SDK classes bypasses this and is a bug.
+- **Dual architecture** — Sylius 2.1+ uses a command/response provider model alongside legacy Payum actions. Both coexist intentionally.
+- **Card saving condition** — a card is only saved when the PayPlug API response includes `metadata['customer_id']`. Absence of this guard is a bug.
+- **`payment_context.cart`** — required in the PayPlug API payload for Oney and Scalapay payments. Missing it causes API rejection.
+- **Distributed lock in `NotifyAction`** — Symfony Lock is used on payment ID to prevent concurrent webhook processing. Do not flag as over-engineering.
+
+## Code Review Dimensions
+
+### Security
+- SQL injection, XSS, CSRF
+- Authentication and authorization flaws
+- Secrets or credentials committed in code
+- Insecure deserialization, path traversal, SSRF
+- Direct calls to PayPlug PHP SDK classes instead of going through `PayPlugApiClient`
+
+### Performance
+- N+1 queries (especially in Sylius entity traversal)
+- Unnecessary memory allocations
+- Algorithmic complexity (O(n²) in hot paths)
+- Missing database indexes
+- Unbounded queries or loops
+- Resource leaks
+
+### Correctness
+- Edge cases: empty input, null, overflow
+- Race conditions and concurrency issues
+- Error handling and propagation
+- Off-by-one errors, type safety
+- `declare(strict_types=1)` must be present in every PHP file
+- For new payment gateways (PPRO pattern): verify the full implementation checklist is covered (gateway factory, form type, resolver decorator, refund provider, templates, service definitions, translations)
+
+### Maintainability
+- Naming clarity, single responsibility, duplication
+- Test coverage: PHPUnit in `tests/PHPUnit/`, Behat in `features/`
+- Documentation for non-obvious logic only — do not flag missing comments on self-explanatory code
+- PHPStan level max compliance; suppressions must go in `ruleset/phpstan-baseline.neon`
+- ECS coding standard based on `sylius-labs/coding-standard`
+
+## Output Format
+
+Rate each dimension: **Good** / **Needs Attention** / **Critical**
+
+List findings with file path and line number. Lead with Critical findings. Include positive observations alongside issues.