[Revinand]

Fixes #612

Why it fails

SchemaGenerator decides whether a parameter is nullable by searching its type string for null (str_contains() in parseParametersInfo(), stripos() on the DocBlock type in getParameterTypeString()). For array{name: string, nickname: string|null} the null of the nickname key matches, so the parameter becomes array|null and the shape is dropped. Shape keys that are unions, such as ?string or int|string, went to mapSimpleTypeToJsonSchema() whole and fell back to object.

Change

• Both checks now use hasNullBranch(), which looks for null among the top-level branches from splitUnion(). A null inside a shape or generic no longer makes the parameter nullable; array{id: int}|null still does.
• parsePropertyDefinition() maps each branch of a key's union, so string|null becomes ["string", "null"], ?string becomes ["null", "string"] and int|string becomes ["integer", "string"].
• A CHANGELOG.md entry under a new 0.9.1 heading.

The third substring check, in getTypeStringFromReflection(), works on the reflection type, which cannot hold a shape, so I left it as is.

Verification

PHP 8.5.11 (composer:2 image), composer install.

• New test testKeepsNullableAndUnionKeysOfArrayShapesInsideTheShape: on main it fails because nullUnionMember gets ['array', 'null'] with empty items. With the change it passes.
• Unit: 2669 tests, integration: 108 tests, all green with the change.
• phpstan and php-cs-fixer fix --dry-run: clean.
• End to end with the stdio server from the issue: on main tools/call returns -32602. With the change tools/list shows the shape and both {"name": "Ada", "nickname": null} and {"name": "Ada", "nickname": "Countess"} are accepted.

Not run

The interop and conformance suites.