feat: Introduce Domain Resolve Strategy

[colazcy]

Current Problem

Currently, Wireproxy resolves domains by randomly selecting an IP address from the DNS results, without differentiating between A (IPv4) and AAAA (IPv6) records. This behavior may cause issues in certain scenarios.

For instance, some websites, such as Google, are sensitive to the request's source IP address. Wireproxy does not prioritize IPv4 or IPv6 address, which can cause the source IP address to switch between the interface's IPv4 and IPv6 address during a single session. This may trigger security checks.

Solution

This PR introduces a configurable DNS resolution strategy to give users control over this behavior.

[Resolve]
ResolveStrategy = auto / ipv4 / ipv6

• ipv4: Prioritize A records.
• ipv6: Prioritize AAAA records .
• auto (Default): If the WireGuard interface has IPv4 address only, it's equivalent to ipv4, otherwise it's equivalent to ipv6.

This PR also corrects indentation in some files as a minor cleanup,

[Neustradamus]

@whyvl: Have you seen this @colazcy PR?

[Copilot]

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