fix(L1): seed imported schedule protocol version

[jackchuma]

What changed? Why?

• Extend ProtocolVersions.initialize to set the minimum packed protocol version atomically with an imported schedule and reject non-zero activation timestamps when that version is zero.
• Plumb protocolVersionsInitialMinimumVersion through the standard and multiproof deployment paths, retaining the config parser's packed-version bound check.
• Preflight the imported minimum version, timestamp ordering, and future-notice invariants before either deployment path broadcasts transactions, including a one-hour buffer for future activations to remain valid while sequential transactions are mined.
• Add regression and deployment coverage, document the new config field, and refresh the ABI and semver snapshots.

This keeps imported activation schedules immediately consumable by nodes, which reject positive activation timestamps paired with protocol version zero.

Notes to reviewers

• Empty and zero-only initial schedules may still leave the minimum protocol version at zero.
• Future activations must provide MIN_NOTICE plus a one-hour deployment buffer during preflight; the initializer retains its exact MIN_NOTICE trust-boundary check.
• Non-zero initial versions retain the existing 128-bit packed-semver bound.
• minimumProtocolVersion remains outside the scheduleId commitment.
• The initializer remains the contract-level trust boundary. Deployment scripts share a preflight helper only because broadcasts are separate transactions and a later revert cannot roll back earlier broadcasts.
• The deployment integration test verifies the resulting schedule and minimum version; there is no duplicate post-deployment readback in the script.

How has it been tested?

• just test
• just test --match-path test/deploy/SystemDeploy.t.sol
• just test --match-path test/L1/ProtocolVersions.t.sol
• just test --match-path test/L1/proofs/AggregateVerifier.t.sol
• just build-no-tests
• just snapshots
• forge fmt --check
• just validate-spacers-no-build

[cb-heimdall]

✅ Heimdall Review Status

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[cb-heimdall]

Review Error for CatfishbillyIII @ 2026-08-27 13:21:15 UTC
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