app/upgrades: add v1.11.1 audit min_disk_free_percent floor

[mateeullahmalik]

Summary

• add a new custom upgrade handler v1.11.1
• enforce audit.params.min_disk_free_percent >= 15 at upgrade execution
• keep behavior monotonic: only raise to floor, never downgrade if governance already set a higher value
• wire v1.11.1 into the central upgrade registry and upgrade tests

Context

Mainnet needs a deterministic, upgrade-time safety floor for audit host disk-free enforcement, without mutating historical v1.11.0 semantics.

Safety / Correctness

• no store key additions/deletions
• runs RunMigrations first, then applies bounded param update
• fails fast if AuditKeeper wiring is missing
• preserves deterministic behavior and minimal blast radius

Files Changed

• app/upgrades/upgrades.go
• app/upgrades/upgrades_test.go
• app/upgrades/v1_11_1/upgrade.go (new)
• app/upgrades/v1_11_1/upgrade_test.go (new)

Tests

Executed:

• go test ./app/upgrades/... ./x/audit/v1/keeper/...

All passed.

[roomote-v0]

Rooviewer   See task

Reviewed all changed files. The upgrade handler correctly enforces a monotonic floor on audit.params.min_disk_free_percent, follows existing upgrade patterns, and has appropriate test coverage. No issues found.

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