feat(native): update set_user calls to use new new_user function output (#13624)

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Relevant vercel preview pages
-
https://sentry-docs-plsrr24j2.sentry.dev/platforms/native/enriching-events/scopes/#configuring-the-scope
-
https://sentry-docs-plsrr24j2.sentry.dev//platforms/native/enriching-events/identify-user/
-
https://sentry-docs-plsrr24j2.sentry.dev/platforms/native/data-management/sensitive-data/#examples

## DESCRIBE YOUR PR
Related to the change in
getsentry/sentry-native#1228

From now on, we provide the `sentry_value_new_user(id, username, email,
ip_address)` function that fills out the correct keys. This should
reduce user error & confusion with what keys are processed by Sentry
(see the [original
issue](getsentry/sentry-native#1225) the
function was added for).

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## PRE-MERGE CHECKLIST

*Make sure you've checked the following before merging your changes:*

- [x] Checked Vercel preview for correctness, including links
- [ ] PR was reviewed and approved by any necessary SMEs (subject matter
experts)
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team](https://github.com/orgs/getsentry/teams/docs)

---------

Co-authored-by: Mischan Toosarani-Hausberger <[email protected]>

Author: JoshuaMoelans

platform-includes/enriching-events/scopes/configure-scope/native.mdx

@@ -5,8 +5,7 @@ The Native SDK maintains all data in a single global scope.
 
 sentry_set_tag("my-tag", "my value");
 
-sentry_value_t user = sentry_value_new_object();
-sentry_value_set_by_key(user, "id", sentry_value_new_int32(42));
-sentry_value_set_by_key(user, "email", sentry_value_new_string("[email protected]"));
+// Set a user with id, username, email, and ip_address
+sentry_value_t user = sentry_value_new_user("42", "Jane Doe", "[email protected]", "{{auto}}");
 sentry_set_user(user);
 ```

platform-includes/enriching-events/set-user/native.mdx

@@ -1,9 +1,10 @@
 ```c
 #include <sentry.h>
 
-sentry_value_t user = sentry_value_new_object();
-sentry_value_set_by_key(user, "ip_address", sentry_value_new_string("{{auto}}"));
-sentry_value_set_by_key(user, "email", sentry_value_new_string("[email protected]"));
+// Set a user with id, username, email, and ip_address
+sentry_value_t user = sentry_value_new_user("42", "Jane Doe", "[email protected]", "{{auto}}");
+// Set additional custom user data
+sentry_value_set_by_key(user, "custom_key", sentry_value_new_string("custom_value"));
 sentry_set_user(user);
 ```
 

platform-includes/sensitive-data/set-user/native.mdx

@@ -1,11 +1,8 @@
-The Native SDK maintains all data in a single global scope.
-
 ```c
 #include <sentry.h>
 
-sentry_value_t user = sentry_value_new_object();
-sentry_value_set_by_key(user, "id", sentry_value_new_int32(client_user->id));
-// OR
-sentry_value_set_by_key(user, "username", sentry_value_new_string(client_user->username));
+// At least one parameter must be non-NULL. In this case, the user value will only 
+// contain the id. username, email, and ip_address will be ignored.
+sentry_value_t user = sentry_value_new_user("42", NULL, NULL, NULL);
 sentry_set_user(user);
 ```