WIP: Readd project support to filestate

changelog/pending/20230128--backend-filestate--the-filestate-backend-now-supports-project-scoped-stacks.yaml

@@ -0,0 +1,10 @@
+changes:
+- type: feat
+  scope: backend/filestate
+  description: |
+    The filestate backend now supports project scoped stacks.
+    Newly initialized storage will automatically use this mode.
+    You can migrate your old state store to enable project support by running `pulumi state upgrade`.
+    Note that this will make the state incompatible with old CLI versions.
+    Old CLI versions will not understand new stacks, but may write stack files to the old locations;
+    new CLIs will warn if they see those files and suggest running `pulumi state migrate` again.

pkg/backend/backend.go

@@ -74,7 +74,7 @@ type StackReference interface {
 	// but that information is not part of the StackName() we pass to the engine.
 	Name() tokens.Name
 
-	// Fully qualified name of the stack.
+	// Fully qualified name of the stack, including any organization, project, or other information.
 	FullyQualifiedName() tokens.QName
 }