[app/proxyman] DomainStrategy support for all outbounds

[Vigilans]

DomainStrategy is a setting in freedom outbound that may convert a domain address to ip address for dialing using v2ray's own DNS. This PR made this setting available to all outbounds, for following reasons:

• For certain cases it would be very useful if an outbound could use v2ray's DNS to resolve its proxy address to use. E.g., to choose between ipv4 or ipv6 address of a domain, if either address has route of better quality.
• Freedom outbound's DomainStrategy's implementation is problematic if underlying transport relies on the domain. E.g. HTTP/2 transport will use the domain in its SNI, but freedom outbound replaces it before calling Dial(), which is too early.

This PR adds a Resolver field to session.Outbound, when set it will resolve the domain right before calling the final system dialer (which will call system resolver for the domain), so we can control the ip to use for e.g. vmess proxy server's address, while preserving the domain semantic for transport layer.

Usage:

{
  "outbounds": [
    {
      "tag": "...",
      "protocol": "vmess",
      "settings": {
        "vnext": [{
          "address": "...", "port": 443,
          "users": [{ "id": "...", "security": "zero", "alterId": 0 }]
        }]
      },
      "domainStrategy": "UseIP", // DNS could use queryStrategy to control whether return IPv4 or IPv6
      "streamSettings": {
        "network": "h2",
        "security": "tls",
        "httpSettings": {
          "host": ["..."],
          "path": "..."
        }
      }
    }
  ]
}

[codecov-commenter]

Codecov Report

Base: 39.21% // Head: 39.12% // Decreases project coverage by -0.10% ⚠️

Coverage data is based on head (236d903) compared to base (83ea1ba).
Patch coverage: 11.42% of modified lines in pull request are covered.

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Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2334      +/-   ##
==========================================
- Coverage   39.21%   39.12%   -0.10%     
==========================================
  Files         617      617              
  Lines       36859    36917      +58     
==========================================
- Hits        14454    14443      -11     
- Misses      20816    20879      +63     
- Partials     1589     1595       +6     

Impacted Files	Coverage Δ
app/proxyman/outbound/handler.go	30.23% <0.00%> (-9.50%)	⬇️
common/session/session.go	70.58% <ø> (ø)
app/proxyman/config.pb.go	17.78% <5.26%> (-0.73%)	⬇️
infra/conf/v4/v2ray.go	38.56% <25.00%> (-0.39%)	⬇️
proxy/freedom/freedom.go	47.31% <25.00%> (+1.85%)	⬆️
transport/internet/dialer.go	50.00% <30.76%> (-8.34%)	⬇️
app/router/command/errors.generated.go	0.00% <0.00%> (-100.00%)	⬇️
app/proxyman/outbound/errors.generated.go	0.00% <0.00%> (-100.00%)	⬇️
common/task/task.go	88.88% <0.00%> (-7.41%)	⬇️
... and 6 more

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