feat(native): local scopes (#15241)

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## DESCRIBE YOUR PR

Adds missing documentation for local scopes introduced earlier in
sentry-native
[0.9.0](https://github.com/getsentry/sentry-native/releases/tag/0.9.0):
- getsentry/sentry-native#1248

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Author: jpnurmi

docs/platforms/native/common/enriching-events/scopes/index.mdx

@@ -35,7 +35,7 @@ routes or controllers.
 As you start using an SDK, a scope and hub are automatically created for you out
 of the box. It's unlikely that you'll interact with the hub directly unless you're
 writing an integration or you want to create or destroy scopes. Scopes, on the
-other hand are more user facing. You can call <PlatformIdentifier name="configure-scope" /> at any point in
+other hand are more user facing. You can call various setters at any point in
 time to modify data stored on the scope. This is useful for doing things like
 [modifying the context](../context/).
 
@@ -53,7 +53,8 @@ For details on how this affects tracing, check out the [Connect Errors With Span
 
 ## Configuring the Scope
 
-The most useful operation when working with scopes is the <PlatformIdentifier name="configure-scope" /> function. It can be used to reconfigure the current scope.
+The Native SDK maintains most data in a global scope, but allows creating transient
+local scopes for capturing individual events.
 
 You can, for instance, add custom tags or inform Sentry about the currently authenticated user.
 

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

@@ -1,6 +1,4 @@
-The Native SDK maintains all data in a single global scope.
-
-```c
+```c {tabTitle:Global Scope}
 #include <sentry.h>
 
 sentry_set_tag("my-tag", "my value");
@@ -9,3 +7,19 @@ sentry_set_tag("my-tag", "my value");
 sentry_value_t user = sentry_value_new_user("42", "Jane Doe", "[email protected]", "{{auto}}");
 sentry_set_user(user);
 ```
+
+```c {tabTitle:Local Scope}
+#include <sentry.h>
+
+sentry_scope_t *scope = sentry_local_scope_new();
+
+sentry_scope_set_tag(scope, "my-tag", "my scoped value");
+
+// 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_scope_set_user(scope, user);
+
+sentry_value_t event = sentry_value_new_event();
+/* ... */
+sentry_capture_event_with_scope(event, scope);
+```