feat(02-02): capture named sessions through a loopback proxy

Record Nuxt/MCP traffic as ordered flows via parity:proxy, pin
loopback upstream, and refuse oversized or credential-shaped fixtures.

Co-authored-by: Cursor <cursoragent@cursor.com>

tide/flow.go

@@ -50,10 +50,14 @@ type Response struct {
 	SHA256   string            `yaml:"sha256,omitempty"`
 }
 
-// CaptureRule maps a JSON path in the response onto a variable name.
+// CaptureRule maps a named source onto a variable name.
 type CaptureRule struct {
-	Path string `yaml:"path"`
-	As   string `yaml:"as"`
+	From     string `yaml:"from,omitempty"`
+	Path     string `yaml:"path,omitempty"`
+	Name     string `yaml:"name,omitempty"`
+	As       string `yaml:"as"`
+	Identity string `yaml:"identity,omitempty"`
+	Category string `yaml:"category,omitempty"`
 }
 
 // NormalizeRule names a per-step normalizer override.