docs: small fixes to workflow constraints chapter (medusajs#11421)

* docs: small fixes to workflow constraints chapter

* add links to plugins in nav

Author: shahednasser

www/apps/book/app/learn/fundamentals/workflows/constructor-constraints/page.mdx

@@ -6,6 +6,10 @@ export const metadata = {
 
 This chapter lists constraints of defining a workflow or its steps.
 
+Medusa creates an internal representation of the workflow definition you pass to `createWorkflow` to track and store its steps. At that point, variables in the workflow don't have any values. They only do when you execute the workflow.
+
+This creates restrictions related to variable manipulations, using if-conditions, and other constraints. This chapter lists these constraints and provides their alternatives.
+
 ## Workflow Constraints
 
 ### No Async Functions

www/apps/book/generated/edit-dates.mjs

@@ -36,7 +36,7 @@ export const generatedEditDates = {
   "app/learn/fundamentals/modules/module-link-directions/page.mdx": "2024-07-24T09:16:01+02:00",
   "app/learn/fundamentals/admin/page.mdx": "2024-10-23T07:08:55.898Z",
   "app/learn/fundamentals/workflows/long-running-workflow/page.mdx": "2025-01-27T08:45:19.028Z",
-  "app/learn/fundamentals/workflows/constructor-constraints/page.mdx": "2024-12-12T15:09:41.179Z",
+  "app/learn/fundamentals/workflows/constructor-constraints/page.mdx": "2025-02-12T13:55:33.437Z",
   "app/learn/fundamentals/data-models/write-migration/page.mdx": "2024-11-11T15:27:59.794Z",
   "app/learn/fundamentals/data-models/manage-relationships/page.mdx": "2025-02-11T15:53:12.541Z",
   "app/learn/fundamentals/modules/remote-query/page.mdx": "2024-07-21T21:20:24+02:00",

www/apps/book/generated/sidebar.mjs

@@ -229,9 +229,9 @@ export const generatedSidebar = [
             "isPathHref": true,
             "type": "link",
             "path": "/learn/fundamentals/modules/modules-directory-structure",
-            "title": "Modules Directory Structure",
+            "title": "Directory Structure",
             "children": [],
-            "chapterTitle": "3.2.1. Modules Directory Structure"
+            "chapterTitle": "3.2.1. Directory Structure"
           },
           {
             "loaded": true,
@@ -592,28 +592,28 @@ export const generatedSidebar = [
             "loaded": true,
             "isPathHref": true,
             "type": "link",
-            "path": "/learn/fundamentals/workflows/variable-manipulation",
-            "title": "Transform Variables",
+            "path": "/learn/fundamentals/workflows/constructor-constraints",
+            "title": "Constructor Constraints",
             "children": [],
-            "chapterTitle": "3.6.1. Transform Variables"
+            "chapterTitle": "3.6.1. Constructor Constraints"
           },
           {
             "loaded": true,
             "isPathHref": true,
             "type": "link",
-            "path": "/learn/fundamentals/workflows/conditions",
-            "title": "When-Then Conditions",
+            "path": "/learn/fundamentals/workflows/variable-manipulation",
+            "title": "Transform Variables",
             "children": [],
-            "chapterTitle": "3.6.2. When-Then Conditions"
+            "chapterTitle": "3.6.2. Transform Variables"
           },
           {
             "loaded": true,
             "isPathHref": true,
             "type": "link",
-            "path": "/learn/fundamentals/workflows/constructor-constraints",
-            "title": "Constructor Constraints",
+            "path": "/learn/fundamentals/workflows/conditions",
+            "title": "When-Then Conditions",
             "children": [],
-            "chapterTitle": "3.6.3. Constructor Constraints"
+            "chapterTitle": "3.6.3. When-Then Conditions"
           },
           {
             "loaded": true,