Merge branch 'json-view/10-view-document' into json-view/11-view-access

Conflicts in See also lists (docs/mkdocs/docs/api/basic_json/begin.md,docs/mkdocs/docs/api/basic_json/cbegin.md,docs/mkdocs/docs/api/basic_json/cend.md,docs/mkdocs/docs/api/basic_json/end.md,docs/mkdocs/docs/api/basic_json/type_name.md), where develop (#5638) and this branch both edited: kept develop's entries and added this branch's basic_json_view links.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

docs/mkdocs/docs/api/basic_json/contains.md

@@ -67,6 +67,18 @@ Logarithmic in the size of the JSON object.
 
     If `#!cpp j.contains(x)` returns `#!c true` for a key or JSON pointer `x`, then it is safe to call `j[x]`.
 
+!!! warning "Deprecation"
+
+    Overload (3) also accepts a [`json_pointer`](../json_pointer/index.md) whose template argument is a `basic_json`
+    specialization (e.g., `nlohmann::json_pointer<nlohmann::json>`) instead of a string type. This is deprecated since
+    version 3.11.0 and will be removed in a future major version; use `basic_json::json_pointer` (for `json`,
+    `nlohmann::json_pointer<std::string>`) instead.
+
+    You should be warned by your compiler with a `-Wdeprecated-declarations` warning if you are using a deprecated
+    function.
+
+    See the [migration guide](../../integration/migration_guide.md#json-pointers) for how to update existing code.
+
 ## Examples
 
 ??? example "Example: (1) check with key"