fix(cacao): derive EIP-1271 ABI signature length from bytes

[SashaMIT]

Summary

• @walletconnect/cacao hardcoded the EIP-1271 ABI bytes length to 0x41 (65), so non-65-byte smart-account signatures were mis-encoded into eth_call calldata.
• Derive length from the hex signature payload (parity with @walletconnect/utils / walletconnect-monorepo).
• Also include SIWE Expiration Time / Not Before / Request ID in formatMessage when present on the CACAO payload.

Test plan

• Existing cacao EIP-1271 mocha tests (need TEST_PROJECT_ID)
• Manual review against monorepo packages/utils/src/signatures.ts length derivation

Made with Cursor

[github-actions]

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