feat(rules): add post-request rules system with response manipulation (#160)

* Add comprehensive post-request rules support for response phase
* Enable response body, status, and header manipulation via set commands
* Refactor command handlers to support both request and response phases
* Implement response modifier system for post-request template execution
* Support response-based rule matching with status and header checks
* Add comprehensive benchmarks for matcher performance
* Refactor authentication and proxying commands for unified error handling
* Support negated conditions with !
* Enhance error handling, error formatting and validation
* Routes: add `rule_file` field with rule preset support
* Environment variable substitution: now supports variables without `GODOXY_` prefix

* new conditions:
  * `on resp_header <key> [<value>]`
  * `on status <status>`
* new commands:
  * `require_auth`
  * `set resp_header <key> <template>`
  * `set resp_body <template>`
  * `set status <code>`
  * `log <level> <path> <template>`
  * `notify <level> <provider> <title_template> <body_template>`

internal/route/rules/io.go

@@ -0,0 +1,36 @@
+package rules
+
+import (
+	"io"
+	"os"
+
+	"github.com/yusing/godoxy/internal/logging/accesslog"
+	gperr "github.com/yusing/goutils/errs"
+)
+
+type noopWriteCloser struct {
+	io.Writer
+}
+
+func (n noopWriteCloser) Close() error {
+	return nil
+}
+
+var (
+	stdout io.WriteCloser = noopWriteCloser{os.Stdout}
+	stderr io.WriteCloser = noopWriteCloser{os.Stderr}
+)
+
+func openFile(path string) (io.WriteCloser, gperr.Error) {
+	switch path {
+	case "/dev/stdout":
+		return stdout, nil
+	case "/dev/stderr":
+		return stderr, nil
+	}
+	f, err := accesslog.NewFileIO(path)
+	if err != nil {
+		return nil, ErrInvalidArguments.With(err)
+	}
+	return f, nil
+}