Add curl-compatible --resolve option

[ryanfowler]

Summary

• add repeatable --resolve HOST:PORT:IP support with curl-compatible wildcard, IPv6, comma-separated, and + forms
• apply static mappings across HTTP/1.1, HTTP/2, HTTP/3, TLS inspection, DoH bootstrap, Alt-Svc, ECH/SVCB, and curl import paths while preserving Host/SNI
• add parser, transport, integration, and resolver race coverage and update CLI documentation

Verification

• go test -v -parallel 8 ./...
• go build .
• staticcheck ./...
• go mod tidy && go mod verify
• go test -race ./internal/resolver