GH-1174 - Improve rendering of trees in reference documentation.

Author: odrotbohm

src/docs/antora/modules/ROOT/pages/fundamentals.adoc

@@ -130,12 +130,12 @@ Let us have a look at an example arrangement (icon:plus-circle[role=green] denot
 [source, subs="+specialchars, macros"]
 ----
 icon:cubes[] Example
-└─ icon:folder[] src/main/java
+╰─ icon:folder[] src/main/java
    ├─ icon:cube[] example                        <1>
-   |  └─ icon:plus-circle[role=green] Application.java
-   └─ icon:cube[] example.inventory              <2>
+   │  ╰─ icon:plus-circle[role=green] Application.java
+   ╰─ icon:cube[] example.inventory              <2>
       ├─ icon:plus-circle[role=green] InventoryManagement.java
-      └─ icon:minus-circle[role=red] SomethingInventoryInternal.java
+      ╰─ icon:minus-circle[role=red] SomethingInventoryInternal.java
 ----
 <1> The application's main package `example`.
 <2> An application module package `inventory`.
@@ -149,16 +149,16 @@ If an application module package contains sub-packages, types in those might nee
 [source, subs="macros, quotes"]
 ----
 icon:cubes[] Example
-└─ icon:folder[] src/main/java
+╰─ icon:folder[] src/main/java
    ├─ icon:cube[] example
-   |  └─ icon:plus-circle[role=green] Application.java
+   │  ╰─ icon:plus-circle[role=green] Application.java
    ├─ icon:cube[] example.inventory
-   |  ├─ icon:plus-circle[role=green] InventoryManagement.java
-   |  └─ icon:minus-circle[role=red] SomethingInventoryInternal.java
+   │  ├─ icon:plus-circle[role=green] InventoryManagement.java
+   │  ╰─ icon:minus-circle[role=red] SomethingInventoryInternal.java
    ├─ **icon:cube[] example.order**
-   |  └─ icon:plus-circle[role=green] OrderManagement.java
-   └─ icon:cube[] example.order.internal
-      └─ icon:plus-circle[role=green] SomethingOrderInternal.java
+   │  ╰─ icon:plus-circle[role=green] OrderManagement.java
+   ╰─ icon:cube[] example.order.internal
+      ╰─ icon:plus-circle[role=green] SomethingOrderInternal.java
 ----
 
 In such an arrangement, the `order` package is considered an API package.
@@ -258,17 +258,17 @@ You achieve that by annotating the `package-info.java` file of those packages wi
 [source, text, subs="macros, quotes"]
 ----
 icon:cubes[] Example
-└─ icon:folder[] src/main/java
+╰─ icon:folder[] src/main/java
    ├─ icon:cube[] example
-   |  └─ icon:plus-circle[role=green] Application.java
+   │  ╰─ icon:plus-circle[role=green] Application.java
    ├─ …
    ├─ icon:cube[] example.order
-   |  └─ icon:plus-circle[role=green] OrderManagement.java
+   │  ╰─ icon:plus-circle[role=green] OrderManagement.java
    ├─ **icon:cube[] example.order.spi**
-   |  ├— icon:coffee[] package-info.java
-   |  └─ icon:plus-circle[role=green] SomeSpiInterface.java
-   └─ icon:cube[] example.order.internal
-      └─ icon:minus-circle[role=red] SomethingOrderInternal.java
+   │  ├— icon:coffee[] package-info.java
+   │  ╰─ icon:plus-circle[role=green] SomeSpiInterface.java
+   ╰─ icon:cube[] example.order.internal
+      ╰─ icon:minus-circle[role=red] SomethingOrderInternal.java
 ----
 
 .`package-info.java` in `example.order.spi`