op-deployer manage: `migrate` and `set-interop-dispute-games` neither broadcast nor dump calldata

### Problem

Two `op-deployer manage` subcommands set up a `KeyedBroadcaster` (via `env.DefaultForkedScriptHost`) but never actually broadcast the resulting transaction, nor do they dump the calldata for a multisig/Safe to execute:

- `op-deployer manage migrate` — `op-deployer/pkg/deployer/manage/migrate.go` (broadcaster at `migrate.go:261`, `DefaultForkedScriptHost` at `migrate.go:272`)
- `op-deployer manage set-interop-dispute-games` — `op-deployer/pkg/deployer/manage/set_interop_dispute_games.go` (broadcaster at `set_interop_dispute_games.go:267`, `DefaultForkedScriptHost` at `set_interop_dispute_games.go:278`)

This is fine for the current forked-simulation/testing use, but neither command is production-ready: these operations are executed by the L1 ProxyAdmin owner (governance multisig), so the real flow needs the **calldata** emitted for signing/execution, not a discarded simulated broadcast.

### Desired outcome

Give both commands a uniform way to produce their governance transaction output — preferably dump the target-address + calldata (the delegatecall payload into OPCM) so it can be handed to a Safe/multisig. Handle both commands the same way to keep `manage` subcommands consistent.

### Context

Surfaced during review of #21518 [here](https://github.com/ethereum-optimism/optimism/pull/21518#discussion_r3586239585). Both commands intentionally mirror each other's structure (`DummyCaller` etches the governance caller in the Solidity script), so a shared approach applies to both.

### Related issues

#20447

Start with op-deployer/pkg/deployer/manage/migrate.go and set_interop_dispute_games.go, focusing on the KeyedBroadcaster and env.DefaultForkedScriptHost locations identified in the issue. Compare their mirrored DummyCaller structures and the discussion in #21518, then define a shared governance-output approach. Done means both commands consistently produce the target address and calldata for Safe or multisig execution.

Written by the indexing model from the issue text.