Reduce flakiness in block checks

[simonlechner]

This PR refactors the blocks rolling and block height checks to be less flaky on CI infrastructure. These changes surfaced an issue the norma configuration when only a single node is present in the network.

[Copilot]

Pull request overview

This PR aims to reduce CI flakiness in network progress checks by (a) making the block-height check sample nodes “at the same time” and (b) making the blocks-rolling check rely on forward observation rather than historical samples, and it also introduces a “network bootstrap” signal to avoid single-node startup deadlocks around doublesign protection.

Changes:

• Add NETWORK_BOOTSTRAP plumbing (Go → Docker env → run_sonic.sh) to conditionally disable DoublesignProtection only when bootstrapping a brand-new single-validator network.
• Refactor blocksRolling to observe progress over a time window (with updated tests).
• Read block heights concurrently in blockHeight checker (with updated tests) to avoid false lag detection due to sequential sampling.

Reviewed changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
scripts/run_sonic.sh	Gate DoublesignProtection disabling behind NETWORK_BOOTSTRAP for single-validator bootstrap.
scenarios/rules_upgrades/allegro_to_brio_mixed_versions.yml	Update scenario description and remove the v2.1.5 node step.
driver/norma/run.go	Adjust node log dumping output formatting and severity.
driver/node/opera.go	Add NetworkBootstrap to node config and pass it to the container env as NETWORK_BOOTSTRAP.
driver/network/local/local.go	Infer and set NetworkBootstrap when creating nodes.
driver/checking/blocks_rolling.go	Replace historical sliding-window logic with forward observation window logic.
driver/checking/blocks_rolling_test.go	Rewrite tests to match the new forward-observation behavior.
driver/checking/block_height.go	Fetch block heights concurrently to reduce skew between node samples.
driver/checking/block_height_test.go	Update mocks/expectations for concurrent RPC calls; add a genesis-within-slack test.