Update on "[compiler] Add DependencyPath optional property"

Adds an `optional: boolean` property to each token in a DependencyPath, currently always set to false. Also updates the equality and printing logic for paths to account for this field.

Subsequent PRs will update our logic to determine which manual dependencies were optional, then we can start inferring optional deps as well.

[ghstack-poisoned]

compiler/packages/babel-plugin-react-compiler/src/ReactiveScopes/MergeReactiveScopesThatInvalidateTogether.ts

@@ -8,7 +8,6 @@
 import {CompilerError} from '..';
 import {
   DeclarationId,
-  DependencyPath,
   InstructionId,
   InstructionKind,
   Place,