wallets: accept base58/base64 Solana serializedTransaction + re-export web3.js types

[alfonso-paella]

Description

Two Solana DX fixes from a customer integrating Solana smart wallets + Jupiter.

1. serializedTransaction encoding trap. The Crossmint API's params.transaction expects base58 — SolanaWallet.sendTransaction bs58-encodes when you pass a VersionedTransaction object, but when you pass serializedTransaction: string it forwarded the value untouched, so base58 was silently required and undocumented. Jupiter returns base64, so those strings failed. (The README even wrongly documented <base64-encoded-transaction>.)

We now auto-detect and normalize. A new util deserializes to validate, so detection is unambiguous:

normalizeSolanaSerializedTransaction(serialized): string
  // try base58 → VersionedTransaction.deserialize(bs58.decode(s))  → return s unchanged (backward compatible)
  // else base64 → VersionedTransaction.deserialize(Buffer.from(s,"base64")) → return bs58.encode(bytes)
  // else throw "Value must be a base58- or base64-encoded Solana transaction"

base58 is tried first, so existing base58 callers are unaffected. JSDoc on SolanaTransactionInput.serializedTransaction / sendTransaction and the README now state both encodings are accepted.

2. @solana/web3.js type clash. @solana/web3.js was pinned exactly (1.98.1) in dependencies while also declared as a peer (^1.98.1). The exact pin makes package managers install a duplicate nested copy for consumers on a different 1.98.x, so their app's VersionedTransaction is not assignable to the SDK's. Least-disruptive, non-breaking fix:

• Relax the dependencies range to ^1.98.1 (matches the peer range) so it dedupes to the consumer's copy.
• Re-export the relevant types from the SDK entrypoint: VersionedTransaction, SolanaTransaction, SolanaKeypair, SolanaPublicKey (aliased to avoid clashing with the SDK's own Transaction).

Breaking-change note: the fully robust single-copy guarantee would be to make @solana/web3.js peer-only (drop it from dependencies). That is a breaking change — the SDK imports web3.js at runtime in several signer files, so consumers not already installing it would break — so it was intentionally avoided in favor of the caret relax + re-export.

Test plan

• New unit tests for normalizeSolanaSerializedTransaction: base58 returned unchanged, base64 converted to the expected base58, invalid input throws.
• Updated SolanaWallet tests: base58 pass-through + a base64 input asserting the API receives the base58 encoding. Test helper createMockSolanaSerializedTransaction now builds a real deserializable VersionedTransaction.
• pnpm --filter @crossmint/wallets-sdk... build, pnpm --filter @crossmint/wallets-sdk test:vitest (652 passed), and pnpm lint all pass locally.

Package updates

• @crossmint/wallets-sdk — minor. Changeset added (.changeset/solana-transaction-encoding.md).

Link to Devin session: https://crossmint.devinenterprise.com/sessions/ef97ae75e32647d8a1aae862ed5f86b8
Requested by: @alfonso-paella

[devin-ai-integration]

Original prompt from Alfonso

# SDK DX: base58/base64 transaction encoding trap + bundled @solana/web3.js type clash

Repo: Crossmint/crossmint-sdk (has an environment blueprint; pnpm build, pnpm lint, wallets-sdk build+test as in the blueprint. Changesets required for packages/ changes: pnpm change:add).

#``# Context (from a customer report — you do NOT have access to the parent session)
A customer integrating Solana smart wallets + Jupiter reported two SDK DX issues:

> 1. The REST reference documents base58 for params.transaction, but the SDK's serializedTransaction input is undocumented and silently expects base58 too, while Jupiter returns base64. A sentence in the SDK docs (or accepting both encodings) would remove the trap.
> 2. The SDK bundles its own copy of ``@solana/web3.js, so the app's `VersionedTransaction` type is not assignable to the SDK's. Passing a string works, but a peer dependency or re-exported types would fix the type clash.

#``# Your task

1. Encoding: Find where the wallets SDK accepts serializedTransaction for Solana. Confirm it expects base58. Choose the smaller, safer improvement: (a) accept both base58 and base64 (auto-detect) OR (b) document the base58 requirement clearly in the SDK reference/JSDoc. Prefer accepting both if it can be done unambiguously and safely; otherwise document. Implement it with tests.
2. web3.js type clash: Investigate how ``@solana/web3.js is declared (dependency vs peerDependency) in the wallets SDK package(s). Evaluate making it a peer dependency and/or re-exporting the relevant transaction types so app-side `VersionedTransaction` is assignable. Implement the least-disruptive fix. Be careful about breaking changes — if making it a peer dep is a breaking change, note it and consider re-exporting types as the non-breaking option.
3. Add a changeset, run pnpm lint and wallets-sdk build+test.

#``# Deliverable
A draft PR (or two, if the two concerns are cleanly separable) against Crossmint/crossmint-sdk. Describe th... (96 chars truncated...)

[changeset-bot]

🦋 Changeset detected

Latest commit: 3993ce5

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

This PR includes changesets to release 9 packages

Name	Type
@crossmint/wallets-sdk	Minor
@crossmint/wallets-quickstart-devkit	Patch
@crossmint/wallets-playground-react	Patch
@crossmint/client-sdk-react-base	Patch
@crossmint/client-sdk-react-native-ui	Patch
@crossmint/client-sdk-react-ui	Patch
@crossmint/wallets-playground-expo	Patch
@crossmint/auth-ssr-nextjs-demo	Patch
@crossmint/client-sdk-nextjs-starter	Patch

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