docs: Add css docs to entries

The various entries were missing the semi-standard
"CSS Nodes" section in their long descriptions. Add
them.

gtk/gtkentry.c

@@ -121,7 +121,7 @@
  * ├── text[.readonly]
  * ├── image.left
  * ├── image.right
- * ├── [progress[.pulse]]
+ * ╰── [progress[.pulse]]
  * ]|
  *
  * GtkEntry has a main node with the name entry. Depending on the properties

gtk/gtkpasswordentry.c

@@ -50,6 +50,20 @@
  *
  * GtkPasswordEntry provides only minimal API and should be used with the
  * #GtkEditable API.
+ *
+ * # CSS Nodes
+ *
+ * |[<!-- language="plain" -->
+ * entry.password
+ * ╰── text
+ *     ├── image.caps-lock-indicator
+ *     ┊
+ * ]|
+ *
+ * GtkPasswordEntry has a single CSS node with name entry that carries
+ * a .passwordstyle class. The text Css node below it has a child with
+ * name image and style class .caps-lock-indicator for the Caps Lock
+ * icon, and possibly other children.
  */
 
 typedef struct {

gtk/gtksearchentry.c

@@ -71,6 +71,17 @@
  * placed inside a #GtkSearchBar. If that is not the case,
  * you can use gtk_search_entry_set_key_capture_widget() to let it
  * capture key input from another widget.
+ *
+ * # CSS Nodes
+ *
+ * |[<!-- language="plain" -->
+ * entry.search
+ * ╰── text
+ * ]|
+ *
+ * GtkSearchEntry has a single CSS node with name entry that carries
+ * a .sarch style class, and the text node is a child of that.
+
  */
 
 enum {