Add logger package documentation

public/docs/packages/logger/interfaces/introduction.md

@@ -0,0 +1,82 @@
+---
+id: logger-interfaces-introduction
+slug: docs/packages/logger/interfaces/introduction
+title: Logger Interfaces Overview
+doc_type: reference
+status: active
+language: en
+owner: docs-team
+last_reviewed: 2026-01-25
+applies_to: ["all"]
+canonical: true
+summary: Overview of interfaces provided by the logger package.
+llm_summary: >
+  The phpnomad/logger package provides one interface: LoggerStrategy, which defines the
+  contract for PSR-3 compatible logging throughout PHPNomad applications. This interface
+  declares methods for all 8 standard log levels plus exception logging.
+questions_answered:
+  - What interfaces does the logger package provide?
+  - What is the LoggerStrategy interface?
+audience:
+  - developers
+  - backend engineers
+tags:
+  - logging
+  - interfaces
+  - reference
+llm_tags:
+  - logger-strategy
+  - psr-3
+keywords:
+  - logger interfaces
+  - LoggerStrategy
+related:
+  - ../introduction
+  - ./logger-strategy
+see_also:
+  - ../traits/introduction
+noindex: false
+---
+
+# Logger Interfaces
+
+The logger package provides one core interface that defines the logging contract for PHPNomad applications.
+
+---
+
+## Available Interfaces
+
+| Interface | Purpose |
+|-----------|---------|
+| [LoggerStrategy](./logger-strategy.md) | PSR-3 compatible logging contract with 8 log levels |
+
+---
+
+## Quick Reference
+
+### LoggerStrategy
+
+The primary interface for all logging operations:
+
+```php
+use PHPNomad\Logger\Interfaces\LoggerStrategy;
+
+class MyService
+{
+    public function __construct(private LoggerStrategy $logger) {}
+
+    public function doSomething(): void
+    {
+        $this->logger->info('Operation started');
+    }
+}
+```
+
+See [LoggerStrategy](./logger-strategy.md) for complete documentation.
+
+---
+
+## See Also
+
+- [Logger Package Overview](../introduction.md) - High-level package documentation
+- [Logger Traits](../traits/introduction.md) - Default implementations