Further adjustment for "API Chaining"

docs/api/chaining.md

-# API CiviChaining
+# APIv3 Chaining
 
 It is now possible to do two API calls at once with the first call feeding into
 the second. E.g. to create a contact with a contribution you can nest the
@@ -8,7 +8,7 @@ it will action the contribution create using the id from the contact create as
 be returned when you do a get.
 
 See [api/v3/examples] within the core source code for a plethora of examples
-(from unit tests) that use API CiviChaining. To start, look at these examples:
+(from unit tests) that use chaining. To start, look at these examples:
 
 -   [APIChainedArray.php]
 -   [APIChainedArrayFormats.php]

mkdocs.yml

@@ -73,13 +73,13 @@ pages:
   # CiviReport: /reference/civireport.md        # page-tree = NEED_NEW_PAGE
   # Payment Processing: /reference/payment.md   # page-tree = NEED_NEW_PAGE
 - API:
-  - API Intro: api/general.md                   # page-tree = DONE
-  - API Usage: api/usage.md                     # page-tree = DONE
-  - API Actions: api/actions.md                 # page-tree = DONE
-  - API Parameters: api/params.md               # page-tree = DONE
-  # API Permissions: api/permissions.md         # page-tree = NEED_NEW_PAGE
-  - API CiviChaining: api/chaining.md
-  # API Changes: api/changes.md                 # page-tree = NEED_NEW_PAGE
+  - APIv3 Intro: api/general.md                   # page-tree = DONE
+  - APIv3 Usage: api/usage.md                     # page-tree = DONE
+  - APIv3 Actions: api/actions.md                 # page-tree = DONE
+  - APIv3 Parameters: api/params.md               # page-tree = DONE
+  # APIv3 Permissions: api/permissions.md         # page-tree = NEED_NEW_PAGE
+  - APIv3 Chaining: api/chaining.md
+  # APIv3 Changes: api/changes.md                 # page-tree = NEED_NEW_PAGE
 - Hooks:
   - Using hooks: hooks.md                        # page-tree = NEED_PAGE_MOVE to /hooks/usage.md
   - Setup: