docs: add changelog entries for handleRequest refactor and BC break

Author: gr8man

user_guide_src/source/changelogs/v4.7.5.rst

@@ -14,6 +14,8 @@ Release Date: Unreleased
 BREAKING
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+- **CodeIgniter:** ``storePreviousURL()`` now checks ``$this->request instanceof IncomingRequest`` instead of using ``method_exists($this->request, 'isAJAX')``. Previously, any request object with an ``isAJAX()`` method was accepted; now only ``IncomingRequest`` instances are checked. If you use a custom request class that implements ``isAJAX()``, ensure it extends ``IncomingRequest``.
+
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 Message Changes
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@@ -22,6 +24,9 @@ Message Changes
 Changes
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+- **CodeIgniter:** Fixed a bug where ``gatherOutput()`` could be called twice when ``startController()`` returned a ``ResponseInterface`` (e.g., from filter attributes or closure routes).
+- **CodeIgniter:** Changed ``is_object($this->controller) && $this->controller::class === 'Closure'`` to ``$this->controller instanceof Closure`` for consistency and type safety.
+
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 Deprecations
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