feat: add zod runtime validation for simple account

[avasisht23]

Pull Request Checklist

• Did you add new tests and confirm existing tests pass? (yarn test)
• Did you update relevant docs? (docs are found in the site folder, see guidleines below)
• Do your commits follow the Conventional Commits standard?
• Does your PR title also follow the Conventional Commits standard?
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PR-Codex overview

Detailed summary

• Added SimpleSmartAccountParamsSchema function in packages/core/src/account/schema.ts to create a schema for simple smart account parameters.
• Modified packages/core/src/index.ts to export SimpleSmartAccountParamsSchema.
• Modified packages/core/src/account/__tests__/simple.test.ts to add a test for runtime validation of invalid index.
• Modified packages/core/src/account/types.ts to import SimpleSmartAccountParamsSchema and update the SimpleSmartAccountParams type.
• Modified packages/core/src/account/simple.ts to import SimpleSmartAccountParamsSchema and update the constructor to validate the params using the schema.

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[avasisht23]

Current dependencies on/for this PR:

• development
  • PR feat: remove sub-account support for light account #185
    • PR feat: add zod runtime validation for base account #186
      • PR feat: add zod runtime validation for alchemy provider #187
        • PR feat: add zod runtime validation for ethers adapter provider #188
          • PR feat: add zod runtime validation for simple account #189 👈

This stack of pull requests is managed by Graphite.