docs: correct the Logger override guidance

v3.0/packages/logger/contracts.md

@@ -16,7 +16,7 @@ The Logger package is small, but a few runtime contracts matter when you build o
 - `debug()`
 - `log()`
 
-Each method takes the message as `string|Stringable $message` and an optional `array $context`; `log()` takes the level first. A class that extends `Logger` and overrides these methods must declare the same parameter type.
+Each method takes the message as `string|Stringable $message` and an optional `array $context`; `log()` takes the level first. A class that extends `Logger` and overrides these methods keeps working with no parameter type or with `string|Stringable`; PHP rejects an override that narrows the type, for example to `string`.
 
 But the package does not validate arbitrary custom level strings in `log()`.
 

v3.0/upgrade-guide.md

@@ -12,17 +12,7 @@ This guide summarizes the changes to make when you upgrade a Quantum project. It
 
 **Symfony 6.4.** `symfony/console`, `symfony/var-dumper` and `symfony/var-exporter` are on the `^6.4` line. Commands that extend `Quantum\Console\CliCommand` need no change. A class in your application that extends a Symfony class directly may need Symfony 6's stricter return types.
 
-**`psr/log` 2 or 3.** The framework accepts both, so an application that uses `psr/log` 3 (for example through Monolog 3) can now install it. The nine PSR-3 methods of `Quantum\Logger\Logger` declare `string|Stringable $message`. A class that extends `Logger` and overrides them must declare the same type:
-
-```php
-use Stringable;
-
-// before
-public function info($message, array $context = []): void
-
-// after
-public function info(string|Stringable $message, array $context = []): void
-```
+**`psr/log` 2 or 3.** The framework accepts both, so an application that uses `psr/log` 3 (for example through Monolog 3) can now install it. The nine PSR-3 methods of `Quantum\Logger\Logger` declare `string|Stringable $message`. A class that extends `Logger` and overrides them needs no change when its parameter has no type or is `string|Stringable`. PHP rejects an override that narrows the type, for example to `string`, and it did before as well.
 
 **Return types.** `Quantum\HttpClient\ResponseHeaders` declares `offsetGet()`, `current()` and `key()` as `mixed`, and `Quantum\Session\Adapters\Database\DatabaseHandler::gc()` as `int|false`, because PHP 8.1 expects them. A subclass that overrides these methods must declare compatible return types. `gc()` also returns the number of deleted sessions now; it returned `0` after any successful delete.