feat(shared): extract client/server pure helpers into @jerapah-flow/shared

Share profile merge, workflow filename/path helpers, HTTP_METHODS (with OPTIONS), and isPlainObject so web and server stop drifting. Core script sandboxes keep local isPlainObject copies.

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

packages/server/workflow-duplicate.js

@@ -1,36 +1,14 @@
 import yaml from "yaml";
+import {
+  ensureWorkflowFilename,
+  suggestCopyFilename,
+} from "@jerapah-flow/shared";
 import {
   newWorkflowFilename,
   workflowFileStem,
 } from "./workflow-normalize.js";
 
-export function ensureWorkflowFilename(file) {
-  const trimmed = String(file ?? "").trim();
-  if (!trimmed) return "";
-  return /\.ya?ml$/i.test(trimmed) ? trimmed : `${trimmed}.yaml`;
-}
-
-/**
- * Legacy human-readable copy name (kept for UI hints).
- * @param {string} file
- * @param {string[]} existingFiles
- */
-export function suggestCopyFilename(file, existingFiles = []) {
-  const name = ensureWorkflowFilename(file) || "workflow.yaml";
-  const match = name.match(/^(.*?)(\.ya?ml)$/i);
-  const base = match ? match[1] : name;
-  const ext = match ? match[2] : ".yaml";
-  const existing = new Set(existingFiles);
-
-  const copyMatch = base.match(/^(.*)-copy(?:-(\d+))?$/);
-  const root = copyMatch ? copyMatch[1] : base;
-  const candidate = (i) =>
-    i <= 1 ? `${root}-copy${ext}` : `${root}-copy-${i}${ext}`;
-
-  let n = copyMatch ? Number(copyMatch[2] || 1) + 1 : 1;
-  while (existing.has(candidate(n))) n += 1;
-  return candidate(n);
-}
+export { ensureWorkflowFilename, suggestCopyFilename };
 
 /**
  * UUID-based duplicate filename (default for new duplicates).