fix(typescript): sequence async websocket decompression to prevent ou…

[rohanranjan0902]

Description of Changes

This PR fixes a bug in the TypeScript SDK where compressed WebSocket frames could be delivered out of order to the DbConnection.

Previously, WebsocketDecompressAdapter bound an async handler directly to ws.onmessage. Because decompression time scales with payload size, a small frame could finish decompressing before a larger frame that arrived earlier, resulting in out-of-order delivery and silent client cache corruption.

To fix this, this PR decouples the concurrent decompression step from the delivery callback by sequencing the deliveries through a Promise chain (tail). The decompression itself still occurs concurrently, but the hand-off to the SDK is strictly ordered by the socket arrival sequence.

Fixes #5730

API and ABI breaking changes

None. This is an internal fix to the WebSocket adapter.

Expected complexity level and risk

2

The change modifies the asynchronous delivery logic of the WebSocket adapter. While the logic is well-contained, Promise chaining can be a bit subtle. We made sure to properly handle rejections so that decompression errors (e.g. "Incomplete compressed input") don't surface as unhandled rejections and will still correctly close the socket.

Testing

• Verified the TypeScript bindings compile without errors via pnpm run build locally.
• Reviewers can run the standalone reproduction script provided in Issue TypeScript SDK: WebSocket frames are delivered out of order under compression, silently corrupting the client cache #5730 to verify that the cache miss rate drops to 0.

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