[processing] Pass algorithm configuration on run

Because if it's not passed here, it's basically like writing it to /dev/null right from the beginning.

Author: m-kuhn

python/core/processing/qgsprocessingalgorithm.sip.in

@@ -276,7 +276,7 @@ Returns true if this algorithm generates HTML outputs.
 %End
 
     QVariantMap run( const QVariantMap &parameters,
-                     QgsProcessingContext &context, QgsProcessingFeedback *feedback, bool *ok /Out/ = 0 ) const;
+                     QgsProcessingContext &context, QgsProcessingFeedback *feedback, bool *ok /Out/ = 0, const QVariantMap &configuration = QVariantMap() ) const;
 %Docstring
 Executes the algorithm using the specified ``parameters``. This method internally
 creates a copy of the algorithm before running it, so it is safe to call

src/core/processing/models/qgsprocessingmodelalgorithm.cpp

@@ -288,7 +288,7 @@ QVariantMap QgsProcessingModelAlgorithm::processAlgorithm( const QVariantMap &pa
 
       bool ok = false;
       std::unique_ptr< QgsProcessingAlgorithm > childAlg( child.algorithm()->create( child.configuration() ) );
-      QVariantMap results = childAlg->run( childParams, context, &modelFeedback, &ok );
+      QVariantMap results = childAlg->run( childParams, context, &modelFeedback, &ok, child.configuration() );
       childAlg.reset( nullptr );
       if ( !ok )
       {

src/core/processing/qgsprocessingalgorithm.cpp

@@ -371,9 +371,9 @@ bool QgsProcessingAlgorithm::hasHtmlOutputs() const
   return false;
 }
 
-QVariantMap QgsProcessingAlgorithm::run( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback, bool *ok ) const
+QVariantMap QgsProcessingAlgorithm::run( const QVariantMap &parameters, QgsProcessingContext &context, QgsProcessingFeedback *feedback, bool *ok, const QVariantMap &configuration ) const
 {
-  std::unique_ptr< QgsProcessingAlgorithm > alg( create() );
+  std::unique_ptr< QgsProcessingAlgorithm > alg( create( configuration ) );
   if ( ok )
     *ok = false;
 

src/core/processing/qgsprocessingalgorithm.h

@@ -311,7 +311,7 @@ class CORE_EXPORT QgsProcessingAlgorithm
      * if you need to run algorithms from a background thread, or use the QgsProcessingAlgRunnerTask class.
      */
     QVariantMap run( const QVariantMap &parameters,
-                     QgsProcessingContext &context, QgsProcessingFeedback *feedback, bool *ok SIP_OUT = nullptr ) const;
+                     QgsProcessingContext &context, QgsProcessingFeedback *feedback, bool *ok SIP_OUT = nullptr, const QVariantMap &configuration = QVariantMap() ) const;
 
     /**
      * Prepares the algorithm for execution. This must be run in the main thread, and allows the algorithm