chore(svm): upgrade @solana/kit to v5.1.0

[tenequm]

Description

Completes the @solana/kit v5 migration for @x402/svm, following the approach established in #663.

Background

PR #663 upgraded the legacy x402 package to @solana/kit v5. However, PR #705 (v2 architecture restructure) was developed in parallel and introduced the new @x402/svm package still pinned to kit v2. This creates a dependency conflict for projects using kit v5.

This PR brings @x402/svm to parity with the legacy package by upgrading to kit v5.1.0.

Dependency Changes

Package	Before	After
@solana/kit	^2.1.1	^5.1.0
@solana-program/compute-budget	^0.8.0	^0.11.0
@solana-program/token	^0.5.1	^0.9.0
@solana-program/token-2022	^0.4.2	^0.6.1
@solana/transaction-confirmation	^2.1.1	Removed
zod	^3.24.2	Removed
@scure/base	dependency	devDependency

Why these changes

@solana/kit v5.1.0 includes an important bug fix in @solana/transaction-confirmation (PR #1003) where transaction errors during confirmation might not be thrown properly.

Removed dependencies:

• @solana/transaction-confirmation - Not imported anywhere in the source; already re-exported from @solana/kit
• zod - Not imported anywhere; comes as transitive dependency from @x402/core
• @scure/base - Moved to devDependencies since it's only used in integration tests

Code changes:

• Removed explicit as CompiledTransactionMessage type casts in utils.ts and facilitator schemes
• In kit v5, getCompiledTransactionMessageDecoder().decode() returns the exact type expected by decompileTransactionMessage(), making the casts unnecessary

Files Modified

• packages/mechanisms/svm/package.json - Dependency updates
• packages/mechanisms/svm/src/utils.ts - Remove type cast
• packages/mechanisms/svm/src/exact/facilitator/scheme.ts - Remove type cast
• packages/mechanisms/svm/src/exact/v1/facilitator/scheme.ts - Remove type cast
• pnpm-lock.yaml - Lockfile update

Tests

All 109 unit tests pass:

pnpm test

 ✓ test/unit/types.test.ts (5 tests)
 ✓ test/unit/signer.test.ts (9 tests)
 ✓ test/unit/client.test.ts (5 tests)
 ✓ test/unit/server.test.ts (14 tests)
 ✓ test/unit/v1/index.test.ts (4 tests)
 ✓ test/unit/index.test.ts (37 tests | 9 skipped)
 ✓ test/unit/v1/facilitator.test.ts (6 tests)
 ✓ test/unit/facilitator.test.ts (6 tests)
 ✓ test/unit/server.moneyParser.test.ts (28 tests)
 ✓ test/unit/v1/client.test.ts (4 tests)

 Test Files  10 passed (10)
      Tests  109 passed | 9 todo (118)

Build and type-check pass:

pnpm build  # Success
npx tsc --noEmit  # No errors

Checklist

• I have formatted and linted my code
• All new and existing tests pass
• My commits are signed (required for merge)

[cb-heimdall]

✅ Heimdall Review Status

Requirement	Status	More Info
Reviews	✅ 1/1	Denominator calculation Show calculation 1 if user is bot 0 1 if user is external 0 2 if repo is sensitive 0 From .codeflow.yml 1 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 1 1 1 if commit is unverified 0 Sum 1

[vercel]

@tenequm is attempting to deploy a commit to the Coinbase Team on Vercel.

A member of the Team first needs to authorize it.

[phdargen]

Good catch @tenequm and thanks for the update! Looks good and the e2e tests also ran without issue