Make request executor creation eager by default

[tobias-tengler]

No description provided.

[codecov]

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[Copilot]

Pull Request Overview

This PR implements eager initialization of Hot Chocolate request executors by default. Previously, schema and request executor creation was lazy (deferred until first request), but now they are created during server startup to improve initial request performance and provide faster feedback on schema errors.

• Makes request executor creation eager by default instead of lazy
• Replaces InitializeOnStartup() API with new AddWarmupTask() API for better warmup task control
• Updates documentation to reflect the new eager initialization behavior

Reviewed Changes

Copilot reviewed 34 out of 34 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
website/src/docs/hotchocolate/v16/server/warmup.md	Rewrites documentation to reflect eager initialization as default behavior
website/src/docs/hotchocolate/v16/migrating/migrate-from-15-to-16.md	Adds migration guide for eager initialization changes
src/HotChocolate/Core/src/Types/SchemaOptions.cs	Adds LazyInitialization property to control initialization behavior
src/HotChocolate/Core/src/Execution/RequestExecutorManager.cs	Removes warmup-specific logic and simplifies executor creation
src/HotChocolate/Core/src/Execution.Abstractions/Execution/IRequestExecutorWarmupTask.cs	Adds ApplyOnlyOnStartup property to warmup task interface
Multiple test files	Updates tests to use new AddWarmupTask() API instead of InitializeOnStartup()
AspNetCore/Warmup files	Refactors warmup service to support new eager initialization pattern

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[Copilot]

The comment appears to be cut off. 'laz' should be completed to 'lazily'.

Suggested change

	/// laz
	/// lazily

[Copilot]

The summary is missing the subject that should be initialized lazily. It should specify what gets initialized (e.g., 'request executor' or 'schema').

Suggested change

	/// Gets or sets whether the should be initialized lazily.
	/// Gets or sets whether the schema and request executor should be initialized lazily.