[schlessera]

Closes #173

What changed

A service can now pass a Presenter with View::render() and render_partial(), and the template calls its methods on $this. Only methods declared on an interface that extends Presenter are forwarded. String and stringable results are escaped like context properties, SafeHtml passes through as markup, and anything else comes back unchanged, so a boolean can drive an if. A partial inherits its parent's presenter unless given its own, and the presenter only holds for its own render. These calls fail the view through the existing debug/production policy: one with no presenter, one to an undeclared method, and any call on a presenter that declares a method the scope shadows (raw, render_partial, magic methods). The loop sample now reads its header through a PostHeader presenter (QueriedPostHeader, bound in the composition root and injected into SampleLoopService), and docs/patterns.md has a new "I need a template to ask for more than its context" section.

Why this shape

Ruled on #145 (revised decision, 2026-10-24). The earlier ruling put one plugin-wide ViewContext in the view factories. That object would grow with every subsystem, let every template call every method, make infrastructure views depend on the domain, and need #149's injector fix. Passing the presenter with the render keeps each template's contract to what its service gives it. No constructor, factory or injector changes.

Proof

composer test      # PHP 8.3: OK (626 tests); PHP 7.4 (dependencies resolved for 7.4): OK, 5 skipped
composer lint      # phpcs, PHPStan level max, Psalm, PHPStan rule tests: all clean on PHP 8.3

• With /** @var TemplateScope&PostHeader $this */ in place, a misspelt $this->titel() in views/test-loop-service.php is reported by both PHPStan (method.notFound) and Psalm (UndefinedInterfaceMethod).
• An independent review (gpt-6-astra) found four real issues, all fixed in this PR:
  • The presenter leaked past its render, so a nested render of the same view changed which presenter later partials inherited. It is now restored in finally.
  • The reserved-name test passed without the guard.
  • The result tests compared printed output rather than types.
  • A doc citation was stale.
• Mutation checks: removing the presenter restore fails 2 tests, and removing the reserved-name guard fails 2 tests.

Checklist

• composer test and composer lint pass locally, and CI is green on the current head.
• Every acceptance criterion from the issue is met, or the gap is named below.
• Nothing a generated plugin relies on changed, or the issue carries breaking and a ruling.
• Docs and inline comments reflect the change, or nothing documented moved.

Anything left open

Breaking for custom View implementations, which must accept the new optional $presenter parameters. #175 records that the View interface still requires stdClass.