feat(zeronet): bump Cobalt activation parameters

[0xth4nh]

Summary

Adds a fast-follow Zeronet task that updates the ProtocolVersions registry after #790:

• delays Cobalt activation from September 16, 2026 at 16:00 UTC to 18:00 UTC
• raises the minimum protocol version from v1.3.2 to v1.4.0
• asserts the ProxyAdmin owner, current values, schedule length, freeze window, and schedule commitment before and after execution

The transaction contains two calls from the ProxyAdmin owner Safe:

1. ProtocolVersions.setTimestamp(12, 1789581600)
2. ProtocolVersions.setMinimumProtocolVersion(79228162588051313888382156800)

Execution ordering

#790 has executed and initialized the ProtocolVersions proxy at 0x30e172aaC675c9fe5A64792F92C9fD4d3E7cA9Da (transaction).

The fast-follow must execute strictly before September 16, 2026 at 15:00 UTC, when the existing 16:00 UTC activation enters its one-hour freeze window.

Testing

• forge fmt --check script tasks/2026-09-15-bump-cobalt-activation-parameters/script
• forge build
• forge build tasks/2026-09-15-bump-cobalt-activation-parameters/script/BumpCobaltActivationParameters.s.sol
• git diff --check

Zeronet validation files are committed for the Coinbase and Security Council signer Safes.

[cb-heimdall]

✅ Heimdall Review Status

Requirement	Status	More Info
Reviews	✅ 2/2	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 2 Additional review requirements Show calculation Max 0 0 From CODEOWNERS 0 Global minimum 0 Max 2 2 1 if commit is unverified 0 Sum 2

Approved review 5215213645 from jackchuma is now dismissed due to new commit. Re-request for approval.