fix: wasm-ton parser gaps and tx id computation

[lcovar]

• Parse withdraw amount from SingleNominator and Whales withdrawal message bodies, exposed as withdrawAmount on ParsedSendAction
• Fix Transaction.id() to use cell hash instead of SHA-256 of BOC bytes, matching TON blockchain convention and TonWeb behavior
• Expose withdrawAmount in JS via try_into_js_value and parser.ts types
• Strengthen transaction tests to assert exact id and withdrawAmount values

BTC-3246

[OttoAllmendinger]

it's probably time to make this a struct

[Copilot]

Pull request overview

This PR fixes TON transaction parsing gaps around staking withdrawals and aligns Transaction.id() with TON ecosystem conventions by computing the root cell hash (rather than hashing BOC bytes), then exposes the new parsed withdrawAmount field through the WASM-to-JS boundary with strengthened tests.

Changes:

• Parse withdraw_amount from Whales + SingleNominator withdrawal message bodies and expose it on ParsedSendAction (Rust + JS types).
• Update Transaction.id() to use the root cell hash from the originally parsed root cell.
• Expand Rust and JS test coverage to assert exact IDs and withdrawal amounts.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/wasm-ton/test/transaction.ts	Adds JS tests for exact transaction IDs and withdrawAmount parsing expectations.
packages/wasm-ton/src/wasm/try_into_js_value.rs	Exposes withdrawAmount in the JS object conversion for ParsedSendAction.
packages/wasm-ton/src/transaction.rs	Implements cell-hash-based transaction IDs and adds Rust tests asserting expected IDs.
packages/wasm-ton/src/parser.rs	Extends message-body parsing to extract withdrawal amounts for specific opcodes.
packages/wasm-ton/js/parser.ts	Updates TS types to include optional withdrawAmount?: bigint.

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[Copilot]

The comment says the “re-serialized cell hash” is what the old buggy code computed, but prior to this change Transaction::id() was SHA-256 of the BOC bytes (not a cell hash). Please update the wording to avoid misleading future readers (e.g., describe it as a naive/alternative implementation based on message.to_cell() rather than “old code”).

Suggested change

	// The re-serialized cell hash (what the old buggy code computed)
	let reserialized_hash = tx
	.message
	.to_cell(())
	.map(|cell| base64::engine::general_purpose::URL_SAFE.encode(cell.hash()))
	.unwrap();
	// The original cell hash (what we now use)
	// The hash of a naively re-serialized message cell produced via `message.to_cell()`.
	let reserialized_hash = tx
	.message
	.to_cell(())
	.map(|cell| base64::engine::general_purpose::URL_SAFE.encode(cell.hash()))
	.unwrap();
	// The hash derived from the original parsed cell, which `Transaction::id()` returns.

addressed