Add requester type info to DI missing-instance exception

[Red-Cat-Fat]

Motivation

• Improve diagnostics when the DI system fails to resolve a dependency by including the type that requested the missing instance in the thrown exception message.

Description

• Extended NotFoundInstanceOrCreateException to store RequesterType and include it in the formatted message when available.
• Propagated requester metadata from the Injector into the resolve context using RequesterTypeContextKey so the container knows which type initiated the parameter resolution.
• Updated ApplicationContainer.GetSingle to extract the requester type from the context and pass it into the NotFoundInstanceOrCreateException when throwing.
• Added a unit test GivenApplicationContainer_WhenInjectNotContainInstance_ThenCatchRequesterTypeInException to validate RequesterType is populated on injection failure.

Testing

• Ran git diff --check to validate workspace changes with no whitespace/patch issues and it passed.
• Updated NUnit test coverage in ExceptionDiContainerTests.cs, but the Unity/NUnit test runner was not executed in this environment so tests were not run here.
• No automated runtime/unit tests were executed due to lack of a Unity test runner in this environment.

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Codex Task