fix(apps/rate-limiting): correct AddressWhitelistKeyPrefix from "address-blacklist" to "address-whitelist"

[crStiv]

Description

Fixes incorrect AddressWhitelistKeyPrefix key name that was set to "address-blacklist" instead of "address-whitelist" in the rate-limiting module.

Changes:

• Fixed key prefix from bytes("address-blacklist") to bytes("address-whitelist")
• Added migration v1→v2 to migrate existing whitelist data from old to new key prefix
• Incremented consensus version from 1 to 2
• Added comprehensive migration tests

Migration Strategy:
The migration safely transfers all existing whitelist entries from the incorrect key prefix to the correct one, preserving data integrity.

closes: #8546

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