[Configuration] Deprecate and disable withSetProviders()

[TomasVotruba]

Set providers are now loaded internally, so withSetProviders() is no longer applied. Calling it emits an E_USER_DEPRECATED warning and points to withComposerBased().

Changes

• withSetProviders() is a no-op that warns and returns $this
• Removed the now-dead setGroups / groupLoadedSets plumbing from RectorConfigBuilder
• withComposerBased() only loads defined set-list constants; the deprecated set-group fallback is gone
• Removed the unused SetManager (its group matching always resolved to nothing without providers)

 return RectorConfig::configure()
-    ->withSetProviders(SomeSetProvider::class)
+    ->withComposerBased(symfony: true, doctrine: true)
 ;

SetProviderCollector stays as it is @api for third-party bridges.

https://claude.ai/code/session_015hE4UdetizXAUwE7JKZHX7

[ghostwriter]

Why are features being removed in patch releases?

Please review AI-generated changes for backward-compatible breaks before merging them.

This change disabled every Rector extension that uses set providers.

Eg. https://redirect.github.com/Sylius/SyliusRector/pull/64

[TomasVotruba]

Because it no longer worked, as set providers are long gone. Poor design overriding future changes.
Make sure to subscribe to releases in https://github.com/rectorphp/rector, not to miss these changes before deprecations.

See https://getrector.com/documentation/composer-based-sets#content-make-a-rule-bound-to-a-package-version

This is how the sets were migrated in Laravel Rector:

• Move composer-based set to single config with version-bound rule registration driftingly/rector-laravel#545
• Move Cashier to composer-based set, deprecate Cashier + Livewire set lists driftingly/rector-laravel#546

[ghostwriter]

Deprecations warn developers that an API may be removed or changed in a future major release.

Incompatible API changes should not be introduced in minor or patch releases.

https://semver.org