feat(ledger-suite-orchestrator): disable archiving for newly installed ledger suites

[gregorydemay]

Stacked on #11407. Addresses the review remark about the hardcoded archive options for new suites.

Why

• A token added while archiving is disabled (DEFI-2986) would get a fresh ledger with trigger_threshold: 2_000 and start archiving once past it, reintroducing the double-mint commit point (DEFI-2967) for that token.

What

• Raise the default trigger_threshold for newly installed ledger suites to 4_200_000_000, the value used to disable archiving on the ckBTC ledger (proposal 143757).

🤖 Generated with Claude Code

https://claude.ai/code/session_01S568wBREAARUA9GvGP5JMP

[Copilot]

🟢 Approval recommended

The focused configuration change is correct and adequately tested.

Pull request overview

Disables archiving for newly installed ledger suites by raising the archive trigger threshold.

Changes:

• Sets the default threshold to 4.2 billion blocks.
• Adds a unit test verifying the new default.

File summaries

File	Description
src/scheduler/mod.rs	Updates the default archive threshold.
src/scheduler/tests.rs	Tests the disabled-archiving configuration.

Review details

• Files reviewed: 2/2 changed files
• Comments generated: 0
• Review effort level: Balanced

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[zeropath-ai]

✅ No security or compliance issues detected. Reviewed everything up to 3c279e8.

Security Overview

• 🔎 Scanned files: 4 changed file(s)
• 🔗 Scan Link: https://zeropath.com/app/repositories/783a9bd4-fb4e-4e10-ab3c-c2fb2ddfb92f?scanId=6bf0c66d-80f1-41e0-840f-2f8e54f8aef9&codeScanTypes=PrScan&tab=issues

Detected Code Changes

Change Type	Relevant files
Enhancement	► rs/ethereum/ledger-suite-orchestrator/src/scheduler/mod.rs     + Introduce ARCHIVING_DISABLED_TRIGGER_THRESHOLD constant and use it to set icrc1_archive_options.trigger_threshold ► rs/ethereum/ledger-suite-orchestrator/src/scheduler/tests.rs     + Add tests for icrc1_archive_options to verify archiving is disabled for new ledger suites
Enhancement	► rs/ethereum/ledger-suite-orchestrator/test_utils/src/pocket_ic/flow.rs     + Adjust comments to reflect removal of hard-coded explanatory lines for trigger_threshold in test setup

[mbjorkqvist]

Thanks @gregorydemay!

A few related things we may still want to address:

• The comment in the test_utils here still mention the production value of 2_000 for the trigger_threshold.
• The docs here still assume archiving will be done - a sentence could be added saying that with the current configuration, archiving is (temporarily) disabled.
• A new SNS ledger suite would still have archiving enable, as per the configuration here. This is perhaps worth a discussion regarding if archiving in general should be disabled for SNSs also (upgrade args are currently not supported for SNS ledger suite upgrades, so this is not so straight-forward).

[gregorydemay]

🤖 Thanks @mbjorkqvist! Addressed in 3c279e8:

1. Removed the stale comment in test_utils mentioning the old 2_000 production value.
2. Added a remark to the README lifecycle section stating that archiving is temporarily disabled for newly created ledger suites and why.
3. SNS ledger suites: agreed this is worth a discussion, but it is out of scope for this PR. The double-mint risk motivating this change is specific to the ckEVM minters, and the SNS init configuration is owned by the NNS team.