Add in-depth migration id validations and tests

[timpel-fcs]

Summary

Fixes #2451

• Derive current migration ID from DSO node state (highest sequencer migrationId) via getCurrentMigrationIdFromDsoInfo
• Add migration ID format and increment validation with mutual-presence rules for upgrade time and migration ID
• Extend ConfigField / SetDsoConfigRulesForm with Current migration ID and Current Configuration subtext
• Only submit nextScheduledSynchronizerUpgrade when both upgrade fields are non-empty

Pull Request Checklist

Cluster Testing

• If a cluster test is required, comment /cluster_test on this PR to request it, and ping someone with access to the DA-internal system to approve it.
• If an upgrade test is required, comment /upgrade_test on this PR to request it, and ping someone with access to the DA-internal system to approve it.
• If a hard-migration test is required (from the latest release), comment /hdm_test on this PR to request it, and ping someone with access to the DA-internal system to approve it.
• If a logical synchronizer upgrade test is required (from canton-3.5), comment /lsu_test on this PR to request it, and ping someone with access to the DA-internal system to approve it.

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[timpel-fcs]

@pawelperek-da

[ray-roestenburg-da]

#2451 (comment)

This is a stale issues, this is not relevant anymore now that LSUs are in effect, the change is not needed.