BridgeJS: support imports of JS `Promise` as `async` Swift (#707)

* BridgeJS: support imports of `Promise` JS as `async` Swift

* E2e testing of bridging Promise<interface> returns

* fix formatting

* `JSTypedClosure`-based approach

* Clean up `BridgeJSLink`

* Fix missing `import _Concurrency`

* Fix formatting

* Use `JSTypedClosure` without wrapping the result value

* Make closure parameters as `sending`

* Check more stack ABI types

* Add support for `async` in `@JSFunction`

* Use namespaced import

* Fix missing `fetchWeatherData`

* Bring back `fetchWeatherData`

* Regenerate `fetchWeatherData` bridging code

* BridgeJS: Centralize closure sig collection in BridgeSkeletonWalker

* BridgeJS: Stop spreading isAsync handling outside of CallJSEmission

* BridgeJS: Remove error-prone default effects in thunk generation

* BridgeJSLink: Centralize async handling in ImportedThunkBuilder

* BridgeJS: Remove reundant returnType from `call` family of methods in ImportedThunkBuilder

---------

Co-authored-by: Yuta Saito <[email protected]>

Gate `ExperimentalCustomExecutors` usage behind Swift 6.4 compiler ch…

…eck (#705)

Gate `ExperimentalCustomExecutors` usage behind Swift 6.4 for non-Wasm targets

Seems like it's dropped in Swift 6.3 rc shipped along with Xcode 26.4 RC
in the last minute

Merge pull request #699 from PassiveLogic/kr/protocol-in-closure

BridgeJS: Support protocol types in closure parameters and returns

Merge pull request #693 from PassiveLogic/kr/fix-declare-global-class…

…-stubs

BridgeJS: Include properties and release() in declare global class stubs

Merge pull request #687 from gn-adin-b/adin/property-access-tracing

Add property access tracing to JSTracing

Merge pull request #683 from PassiveLogic/kr/namespace-abi-names

BridgeJS: Include namespace prefix in ABI names for namespace-nested classes and structs

Merge pull request #671 from PassiveLogic/kr/fix-stack-ordering

BridgeJS: Fix stack ordering for optional arrays and dictionaries

BridgeJS: Workaround `@_extern` inlining issue take 2 (#670)

Merge pull request #665 from swiftwasm/fix-swift-class-array

BridgeJS: Fix `Array<@jsclass struct>` support on imported interfaces

Merge pull request #656 from PassiveLogic/kr/jsglue-refactor

NFC: BridgeJS: Refactor JSGlueGen with compositional optional handling and helper consolidation