chore: remove experiment "terraform-directory-reuse" (#21397)

Experiment is no longer required, the new method will be released without an experiment and without a toggle

Main PR is: https://github.com/coder/coder/pull/21398

provisioner/terraform/executor.go

@@ -39,7 +39,7 @@ type executor struct {
 	// cachePath and files must not be used by multiple processes at once.
 	cachePath     string
 	cliConfigPath string
-	files         tfpath.Layouter
+	files         tfpath.Layout
 	// used to capture execution times at various stages
 	timings *timingAggregator
 }

provisioner/terraform/modules.go

@@ -58,7 +58,7 @@ func parseModulesFile(filePath string) ([]*proto.Module, error) {
 // getModules returns the modules from the modules file if it exists.
 // It returns nil if the file does not exist.
 // Modules become available after terraform init.
-func getModules(files tfpath.Layouter) ([]*proto.Module, error) {
+func getModules(files tfpath.Layout) ([]*proto.Module, error) {
 	filePath := files.ModulesFilePath()
 	if _, err := os.Stat(filePath); os.IsNotExist(err) {
 		return nil, nil

provisioner/terraform/serve.go

@@ -160,7 +160,7 @@ func (s *server) startTrace(ctx context.Context, name string, opts ...trace.Span
 	))...)
 }
 
-func (s *server) executor(files tfpath.Layouter, stage database.ProvisionerJobTimingStage) *executor {
+func (s *server) executor(files tfpath.Layout, stage database.ProvisionerJobTimingStage) *executor {
 	return &executor{
 		server:        s,
 		mut:           s.execMut,