feat(web): complete product workflow implementation

web/protocol/modifier.ts

@@ -9,6 +9,36 @@ function fnv1a(value: string): number {
   return hash >>> 0;
 }
 
+export type ModifierParameterMetadata = {
+  key: string;
+  value: unknown;
+  kind: "boolean" | "number" | "string" | "enum" | "object";
+  options?: string[];
+};
+
+/** Derives editable fields from the metadata carried by the authoritative modifier IR. */
+export function modifierParameterMetadata(modifier: ModifierIR): ModifierParameterMetadata[] {
+  return Object.entries(modifier.parameters ?? {}).map(([key, rawValue]) => {
+    // Main may carry a descriptor when RNA exposes enum choices alongside the
+    // current value. Keep the descriptor opaque to callers while deriving the
+    // editable value and choices from it.
+    const descriptor = rawValue && typeof rawValue === "object" && !Array.isArray(rawValue) &&
+      "value" in rawValue && ("kind" in rawValue || "options" in rawValue)
+      ? rawValue as { value: unknown; kind?: ModifierParameterMetadata["kind"]; options?: unknown[] }
+      : undefined;
+    const rawOptions = descriptor?.options ?? (Array.isArray(rawValue) && rawValue.every((entry) => typeof entry === "string") ? rawValue : undefined);
+    const options = rawOptions?.map(String);
+    const value = descriptor?.value ?? (options ? options[0] : rawValue);
+    const kind = descriptor?.kind ?? (
+      typeof value === "boolean" ? "boolean" :
+      typeof value === "number" ? "number" :
+      typeof value === "string" ? (options ? "enum" : "string") :
+      "object"
+    );
+    return { key, value, kind, options: options ?? undefined };
+  });
+}
+
 /** Hashes evaluated modifier identity/state, excluding display timestamps. */
 export function modifierStackHash(stack: readonly ModifierIR[] | undefined): string {
   const canonical = (stack ?? []).map((modifier) => ({