Update doc with the links to concepts (#683)

docs/api.rst

@@ -61,7 +61,7 @@ Data Structures
 Owned Types
 ~~~~~~~~~~~
 
-TODO: owned type description
+See :ref:`owned_types_concept`
 
 .. c:type:: z_owned_slice_t
   
@@ -130,7 +130,7 @@ TODO: owned type description
 Loaned Types
 ~~~~~~~~~~~
 
-TODO: loaned type description
+See :ref:`loaned_types_concept`
 
 .. c:type:: z_loaned_slice_t
 
@@ -199,7 +199,7 @@ TODO: loaned type description
 View Types
 ~~~~~~~~~~~
 
-TODO: view type description
+See :ref:`view_types_concept`
 
 .. c:type:: z_view_string_t
 

docs/concepts.rst

@@ -28,6 +28,8 @@ Zenoh-Pico types fall into these categories:
 - Option structures: `z_xxx_options_t`
 - Enums and plain data structures: `z_xxx_t`
 
+.. _owned_types_concept:
+
 Owned Types `z_owned_xxx_t`
 ---------------------------
 
@@ -47,6 +49,8 @@ the `z_drop` macro. Example:
 Owned objects can be passed to functions in two ways: by moving (`z_moved_xxx_t`) or 
 loaning (`z_loaned_xxx_t`).
 
+.. _loaned_types_concept:
+
 Loaned Types `z_loaned_xxx_t`
 -----------------------------
 
@@ -68,6 +72,8 @@ modify (`z_loaned_xxx_t*`) the object. In both cases, ownership remains with the
     z_drop(z_move(s));
     z_drop(z_move(s1));
 
+.. _moved_types_concept:
+
 Moved types `z_moved_xxx_t`
 ---------------------------
 
@@ -89,6 +95,8 @@ it's not required. Note that `z_drop` itself takes ownership, so `z_move` is als
     }
     // z_drop(z_move(cfg)); // this is safe but useless
 
+.. _view_types_concept:
+
 View Types `z_view_xxx_t`
 -------------------------