feat(typescript/agentkit): major type cleanup

[LufyCZ]

What changed? Why?

• ViemWalletProvider was heavily cleaned up, type-wise. ReadContract function now behaves as expected, SignTypedData is now typed, etc.
• CdpWalletProvider and the parent class EvmWalletProvider have received similar improvements.
• 0x${string} has been replaced with Address and Hex approprietly.
• The Network type has been tightened down considerably, including the chain and network id maps
• Instead of regexes, address checks in zod schemas now use the isAddress function from viem

This PR ensures that the repo is taking advantage of TypeScript a lot more. Many anys and many as type assertions have been removed.

Qualified Impact

• Possible impact on open, but not-yet-merged PRs
• I have tried keeping runtime changes to a minimum, but some were unavoidable. However, tests run, and the repo builds. I have done basic runtime testing as well.
• There should be no "dangerous" impact

[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 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