Wire up numNodes config setting to mission CoreSet creation

[Copilot]

numNodes (--num-nodes) was accepted as a CLI option but never read from MissionContext, so passing it had no effect.

Changes

• 11 mission files: Set nodeCount = context.numNodes on CoreSetOptions for missions that previously inherited the hardcoded default of 3 from CoreSetOptions.GetDefault:

  • MissionBootAndSync, MissionSimplePayment, MissionLoadGeneration, MissionLoadGenerationWithSpikes, MissionLoadGenerationWithTxSetLimit, MissionSorobanInvokeHostLoad, MissionSorobanLoadGeneration, MissionUpgradeTxClusters, MissionProtocolUpgradeWithLoad, MissionValidatorSetup, MissionDatabaseInplaceUpgrade (core set only)

• CLI default: Changed --num-nodes default from 5 to 3 to match the existing CoreSetOptions.GetDefault nodeCount, preserving current behavior when the flag is omitted.

Missions that explicitly set their own nodeCount (catchup, complex topology, mixed-image, etc.) are unchanged.

// Before: numNodes ignored, always 3
MakeLiveCoreSet "core" (CoreSetOptions.GetDefault context.image)

// After: respects --num-nodes
MakeLiveCoreSet "core"
    { CoreSetOptions.GetDefault context.image with
          nodeCount = context.numNodes }