Doc: Describe specifying build and run settings for workspaces

Task-number: QTCREATORBUG-31510
Change-Id: I378674f438c8b16a2c7715f4ca773ada281c64ae
Reviewed-by: David Schulz <david.schulz@qt.io>

dist/changelog/changes-15.0.0.md

@@ -181,8 +181,10 @@ Projects
 
 ### Workspace
 
-* Added the option to add build configurations
-* Added automatic updating of the project tree
+* Added the option to add build configurations into
+  `Projects > Build & Run > Build > Add`
+  ([Documentation](https://doc.qt.io/qtcreator/creator-project-opening.html))
+* Added automatic updating of the project tree in `Projects`
 * Fixed that cloned run configurations were not editable
 
 ### vcpkg

doc/qtcreator/src/external-resources/external-resources.qdoc

@@ -237,3 +237,7 @@
     \externalpage https://www.openssh.com/
     \title OpenSSH
 */
+/*!
+    \externalpage https://code.qt.io/cgit/qt-creator/qt-creator.git/tree/share/qtcreator/jsonschemas/project.json
+    \title project.json
+*/

doc/qtcreator/src/projects/creator-only/creator-projects-opening.qdoc

@@ -56,8 +56,26 @@
     \uicontrol {Open Workspace}.
 
     \QC generates the \e .qtcreator/project.json project file in the directory
-    for setting a project name and file exclusion filters. You can open either
-    the JSON file or the workspace to open the project the next time.
+    for setting a project name and file exclusion filters. You can add build and
+    run settings to the file, as defined by its \l{project.json}{JSON schema}.
+
+    You can open either the JSON file or the workspace to open the project the
+    next time.
+
+    When you add files to the directory or remove them from there, the contents
+    of the \l Projects view are updated automatically.
+
+    To add a build configuration to the workspace:
+
+    \list 1
+        \li Go to \uicontrol Projects > \uicontrol {Build & Run} >
+            \uicontrol Build.
+        \li Select \uicontrol Add > \uicontrol Build.
+        \li Specify build settings.
+    \endlist
+
+    To specify run settings for the workspace, go to \uicontrol Projects >
+    \uicontrol {Build & Run} > \uicontrol Run.
 
     \section1 Re-configure projects
 
@@ -123,5 +141,6 @@
     later. Select the \inlineimage icons/pin.png
     (\uicontrol Pin) button to pin the progress bar back to the toggle button.
 
-    \sa {Manage Kits}{How To: Manage Kits}, {Kits},
+    \sa {Configure projects for building}, {Configure projects for running},
+    {Manage Kits}{How To: Manage Kits}, {Kits}
 */