fix(account-sdk): require factoryData for undeployed smart accounts

[omerbek]

Closes #377.

What changed

• Make getFactoryArgs() throw a clear BaseError when factoryData is missing.
• Add regression coverage for the provided and missing factoryData paths.

Why

When factoryData is undefined, returning { factory, factoryData: undefined } can silently produce no init code for an undeployed account and defer the failure to bundler/EntryPoint simulation. The SDK cannot safely derive Coinbase Smart Account factory data from only a single owner and owner index, so failing early is safer.

Testing

• git diff --check
• corepack yarn workspace @base-org/account test createSmartAccount could not run because the local checkout has no Yarn state/install (Couldn't find the node_modules state file).

[cb-heimdall]

🟡 Heimdall Review Status

Requirement	Status	More Info
Reviews	🟡 0/1	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 1 Sum 2