Add Zcash destination memo validation

[tzarebczan]

Package: Zcash memo support

This is the JS SDK half of a coordinated two-repo package for Zcash memo support.

Companion PR: Near-One/bridge-sdk-rs#276

Summary

Adds a typed destinationMemo field to the core transfer params and validates the Zcash memo size limit at the SDK boundary before downstream services forward the memo into the Rust bridge SDK / CLI path.

This keeps frontend / API callers able to pass the memo field uniformly while the Rust companion PR is responsible for embedding it in the destination Orchard output.

Details

• Adds destinationMemo?: string to TransferParams.
• Adds INVALID_MEMO as a validation error code.
• Validates the UTF-8 byte length with TextEncoder, not JavaScript character count.
• Enforces the 512-byte Zcash memo limit with details containing both byteLength and maxByteLength.
• Adds focused validation tests for:
  • exactly 512 bytes accepted
  • 513 bytes rejected
  • multi-byte UTF-8 counted as bytes
  • undefined memo accepted
• Adds a patch changeset for @omni-bridge/core.

Relationship to Rust PR

The Rust PR adds the actual memo-aware Zcash SDK / CLI paths and embeds the memo in Orchard shielded outputs. This JS PR provides the consumer-facing type and validation layer expected by callers before handing the memo off to that backend path.

Together, the two PRs make Zcash memo support available end-to-end while keeping existing BTC and shared BTC/Zcash paths unchanged.

Validation

• bun pre-commit hook passed:
  • biome check on changed files
  • tsc --build
• node_modules\.bin\biome.exe check packages/core/src/bridge.ts packages/core/src/types.ts packages/core/src/errors.ts packages/core/tests/bridge.test.ts .changeset/zcash-memo-validation.md
• node_modules\.bin\tsc.exe --build
• node_modules\.bin\vitest.exe run packages --pool=threads

All package tests passed locally: 18 test files, 271 tests.

[changeset-bot]

🦋 Changeset detected

Latest commit: 2999fb4

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 7 packages

Name	Type
@omni-bridge/core	Patch
@omni-bridge/btc	Patch
@omni-bridge/sdk	Patch
@omni-bridge/solana	Patch
@omni-bridge/starknet	Patch
@omni-bridge/evm	Patch
@omni-bridge/near	Patch

Not sure what this means? Click here to learn what changesets are.

Click here if you're a maintainer who wants to add another changeset to this PR

[Copilot]

Pull request overview

Adds a typed destinationMemo field to core transfer params and introduces SDK-boundary validation for Zcash memo size (UTF-8 byte length), with accompanying unit tests and a patch changeset for @omni-bridge/core.

Changes:

• Add destinationMemo?: string to TransferParams and export a new validation error code INVALID_MEMO.
• Enforce a 512-byte UTF-8 memo size limit during Bridge.validateTransfer.
• Add focused vitest coverage for accepted/rejected memo lengths (including multi-byte UTF-8).

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
packages/core/src/bridge.ts	Adds Zcash memo byte-length validation in validateTransfer.
packages/core/src/types.ts	Extends TransferParams with an optional destinationMemo field and doc comment.
packages/core/src/errors.ts	Adds INVALID_MEMO to ValidationErrorCode.
packages/core/tests/bridge.test.ts	Adds unit tests for memo validation behavior.
.changeset/zcash-memo-validation.md	Patch changeset entry for @omni-bridge/core.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.