Custom dust collection type in subtensor

[gztensor]

Description

This PR adds a subtensor pallet type implementation for dust collection that reflects dust collection in subtensor TotalIssuance. Also, it adds a migration that syncs total issuance of subtensor pallet to the source of truth in balances pallet.

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Other (please describe):

Checklist

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have run ./scripts/fix_rust.sh to ensure my code is formatted and linted correctly
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules

[github-actions]

AI review — see the sticky summary comment for the verdict and the inline comments below for specific findings.

[github-actions]

[HIGH] Bump spec_version for this runtime behavior change

This changes runtime execution by installing a Balances DustRemoval hook that mutates Subtensor TotalIssuance, but the PR does not bump VERSION.spec_version in runtime/src/lib.rs (it remains 414). Runtime-affecting changes need a new spec_version; otherwise upgraded nodes can consider their native runtime compatible with the existing on-chain Wasm while executing different accounting logic, which is a consensus-safety hazard. Bump spec_version in the same PR.

[github-actions]

🛡️ AI Review — Skeptic (security review)

VERDICT: VULNERABLE

LOW scrutiny: established repo writer, single self-authored commit, no Gittensor allowlist hit; branch feat/account-dust-collection -> devnet-ready.

The diff is small and targeted, with no .github/ or dependency changes. The remaining blocker is release/consensus safety: the PR changes runtime behavior but leaves the runtime version unchanged.

Findings

Sev	File	Finding
HIGH	runtime/src/lib.rs:522	Bump spec_version for this runtime behavior change	inline

Conclusion

This appears to be a legitimate accounting fix, not a malicious PR. It is currently vulnerable because the runtime behavior change must ship with a spec_version bump to avoid native/Wasm compatibility hazards.

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# 🔍 AI Review — Auditor (domain review) has not yet run on this PR.

[github-actions]

🔄 AI review updated — Skeptic: VULNERABLE