checker: use destructuring annotations for binding types

[nooga]

Summary

Teach destructuring declarations to use explicit annotations as the binding source type.

• Contextually type annotated array destructuring initializers before checking element bindings.
• Use annotated object destructuring types when extracting optional properties and defaults.
• Add a smoke script covering annotated tuple and object destructuring.
• Refresh generated compliance docs.

Compat impact

Published TypeScript snapshot: 3341/4928 -> 3342/4928 (+1).

Against the exact local pre-change full dump used for this branch, the best observed push-hook result was 3340/4928 -> 3342/4928 (+2), with suite-order flakiness noted in the TypeScript runner.

Focused wins:

• types/tuple/tupleElementTypes1.ts
• controlFlow/controlFlowDestructuringDeclaration.ts

Validation

• go build ./...
• go build -o paserati-testtsc ./cmd/paserati-testtsc
• go test ./tests -run TestScripts
• Focused paserati-testtsc diffs for types/tuple and controlFlow
• Full paserati-testtsc diff against the local pre-change dump

[mparrett]

Findings apply to both #13 and #14: they point to the same commit/diff.

• [P1] pkg/checker/checker.go:3459: array destructuring still derives binding and rest element types from valueType, not the annotation type. Because contextual typing is only applied when the initializer is an ArrayLiteral, annotated destructuring from any loses the declared tuple types:

  let pair: any = [1, "s"];
  let [a, b]: [number, string] = pair;
  a = "oops"; // accepted on the PR, should be a type error

  Rest has the same issue:

  let v: any = [1, "s"];
  let [a, ...rest]: [number, string] = v;
  rest = [1]; // accepted, but rest should be string[]

• [P2] pkg/checker/checker.go:3615: object destructuring from tuple annotations now gets a new false positive because destructureType may be a TupleType, but this object-like check only accepts ObjectType, ArrayType, or Any.

  let v: any = [1];
  let { 0: x }: [number] = v; // PR errors: cannot destructure non-object type '[number]'

Verification run on the PR branch: go test ./tests -run TestScripts passed.