feat(tabs): add 'programmatic-native' actionOrigin variant

Adds a fourth value to the public `TabSelectedEvent.actionOrigin` union:
`'user' | 'programmatic-js' | 'programmatic-native' | 'implicit'`. The
new origin is reserved for downstream libraries that integrate directly
against `TabsContainer` (Android) or `RNSTabBarController` (iOS) — this
library itself does not produce it.

Plumbed end-to-end:

- Public TS contract + both Android/iOS codegen specs.
- iOS: `RNSTabsActionOriginProgrammaticNative` enum case and the matching
  arm in the conversion helper that maps the Obj-C enum to the codegen
  C++ scoped enum.
- Android: `TabsActionOrigin.PROGRAMMATIC_NATIVE` + `toString()` mapping.

Android visibility widening to make the new origin reachable from
outside the library (iOS already exposes the equivalent surface):

- `TabsContainer` class is now public; constructor stays `internal`
  because it takes the still-`internal` `TabsContainerDelegate`.
  Downstream is expected to obtain the container reference via its own
  integration path (TabsHost.container stays `private`).
- `setContainerOperation(TabsContainerOp)` is replaced with a public
  `setPendingNavigationStateUpdate(TabsNavStateUpdateRequest)` that
  takes the request directly and wraps in `TabSelectOp` internally.
  Naming mirrors `RNSTabBarController.setPendingNavigationStateUpdate:`.
- `performContainerUpdateIfNeeded()` is now public — the flush trigger
  downstream calls after setting a pending update.
- Internal sealed-class machinery (`TabsContainerOp`, `TabSelectOp`)
  stays internal.

Also reformats iOS doc comments in `RNSTabsNavigationState.h` to
per-case style and the `/**\n * ...\n */` form consistently.

Author: kkafar

android/src/main/java/com/swmansion/rnscreens/gamma/tabs/container/TabsActionOrigin.kt

@@ -1,25 +1,30 @@
 package com.swmansion.rnscreens.gamma.tabs.container
 
 import com.swmansion.rnscreens.gamma.tabs.container.TabsActionOrigin.PROGRAMMATIC_JS
+import com.swmansion.rnscreens.gamma.tabs.container.TabsActionOrigin.PROGRAMMATIC_NATIVE
 import com.swmansion.rnscreens.gamma.tabs.container.TabsActionOrigin.USER
 
 /**
  * Origin (actor) that requested a tab transition. Mirrors the public `actionOrigin` event field.
  *
  * - [USER] — direct native UI interaction (tab bar tap).
  * - [PROGRAMMATIC_JS] — JS-initiated request delivered via the `navStateRequest` prop.
+ * - [PROGRAMMATIC_NATIVE] — request initiated from the native side by a downstream library
+ *   integrating directly against [TabsContainer] (not produced by this library itself).
  *
  * The `implicit` origin defined on the public TS API is iOS-only at the moment;
  * Android does not currently produce it.
  */
 enum class TabsActionOrigin {
     USER,
     PROGRAMMATIC_JS,
+    PROGRAMMATIC_NATIVE,
     ;
 
     override fun toString(): String =
         when (this) {
             USER -> "user"
             PROGRAMMATIC_JS -> "programmatic-js"
+            PROGRAMMATIC_NATIVE -> "programmatic-native"
         }
 }

android/src/main/java/com/swmansion/rnscreens/gamma/tabs/container/TabsContainer.kt

@@ -37,7 +37,7 @@ import com.swmansion.rnscreens.utils.RNSLog
 import kotlin.properties.Delegates
 
 @SuppressLint("ViewConstructor") // Created only by us. Should never be restored.
-internal class TabsContainer(
+class TabsContainer internal constructor(
     private val context: Context,
     private val delegate: TabsContainerDelegate,
 ) : FrameLayout(context),
@@ -196,8 +196,8 @@ internal class TabsContainer(
         return insets
     }
 
-    internal fun setContainerOperation(op: TabsContainerOp) {
-        pendingOperation = op
+    fun setPendingNavigationStateUpdate(request: TabsNavStateUpdateRequest) {
+        pendingOperation = TabSelectOp(request)
         invalidationFlags.isSelectedTabInvalidated = true
     }
 
@@ -224,7 +224,7 @@ internal class TabsContainer(
         invalidationFlags.invalidateAll()
     }
 
-    internal fun performContainerUpdateIfNeeded() {
+    fun performContainerUpdateIfNeeded() {
         if (invalidationFlags.any() && isAttachedToWindow) {
             performContainerUpdate()
         }

android/src/main/java/com/swmansion/rnscreens/gamma/tabs/host/TabsHost.kt

@@ -12,7 +12,6 @@ import com.facebook.react.uimanager.ThemedReactContext
 import com.facebook.react.uimanager.UIManagerHelper
 import com.swmansion.rnscreens.gamma.common.colorscheme.ColorScheme
 import com.swmansion.rnscreens.gamma.helpers.getFabricUIManagerNotNull
-import com.swmansion.rnscreens.gamma.tabs.container.TabSelectOp
 import com.swmansion.rnscreens.gamma.tabs.container.TabsActionOrigin
 import com.swmansion.rnscreens.gamma.tabs.container.TabsContainer
 import com.swmansion.rnscreens.gamma.tabs.container.TabsContainerDelegate
@@ -113,7 +112,7 @@ class TabsHost(
 
     internal fun updateJSNavStateRequest(navStateRequest: TabsNavStateUpdateRequest) {
         jsNavStateRequest = navStateRequest
-        container.setContainerOperation(TabSelectOp(navStateRequest.copy()))
+        container.setPendingNavigationStateUpdate(navStateRequest.copy())
     }
 
     private val layoutCallback =

ios/conversion/RNSConversions-Tabs.mm

@@ -242,6 +242,8 @@ UITabBarControllerMode UITabBarControllerModeFromRNSTabBarControllerMode(RNSTabB
       return User;
     case RNSTabsActionOriginProgrammaticJs:
       return ProgrammaticJs;
+    case RNSTabsActionOriginProgrammaticNative:
+      return ProgrammaticNative;
     case RNSTabsActionOriginImplicit:
       return Implicit;
   }

ios/tabs/host/RNSTabsNavigationState.h

@@ -6,24 +6,40 @@ NS_ASSUME_NONNULL_BEGIN
 
 /**
  * Origin (actor) that requested a tab transition. Mirrors the public `actionOrigin` event field.
- *
- * - [User] direct native UI interaction (tab bar tap, drag-and-drop).
- * - [ProgrammaticJs] JS-initiated request delivered via the `navStateRequest` prop.
- * - [Implicit] platform side effect not attributable to an explicit actor — UIKit changed the selection
- *   as a side effect of another operation (e.g. More navigation controller disappearing during a
- *   horizontal size class transition on iPad).
  */
 typedef NS_ENUM(NSInteger, RNSTabsActionOrigin) {
+  /**
+   * Direct native UI interaction (tab bar tap, drag-and-drop).
+   */
   RNSTabsActionOriginUser = 0,
+  /**
+   * JS-initiated request delivered via the `navStateRequest` prop.
+   */
   RNSTabsActionOriginProgrammaticJs,
+  /**
+   * Request initiated from the native side by some actor, e.g. a downstream
+   * library integrating directly against `RNSTabBarController`.
+   */
+  RNSTabsActionOriginProgrammaticNative,
+  /**
+   * Platform side effect not attributable to an explicit actor — UIKit changed the selection
+   * as a side effect of another operation (e.g. More navigation controller disappearing during a
+   * horizontal size class transition on iPad).
+   */
   RNSTabsActionOriginImplicit,
 };
 
-/** Reason why a navigation state update was rejected by the container. */
+/**
+ * Reason why a navigation state update was rejected by the container.
+ */
 typedef NS_ENUM(NSInteger, RNSTabsNavigationStateRejectionReason) {
-  /** The update's provenance is based on a stale state. */
+  /**
+   * The update's provenance is based on a stale state.
+   */
   RNSTabsNavigationStateRejectionReasonStale = 0,
-  /** The requested tab is already selected. */
+  /**
+   * The requested tab is already selected.
+   */
   RNSTabsNavigationStateRejectionReasonRepeated,
 };
 
@@ -36,11 +52,15 @@ typedef NS_ENUM(NSInteger, RNSTabsNavigationStateRejectionReason) {
  */
 @interface RNSTabsNavigationState : NSObject
 
-/** Screen key of the currently selected tab. */
+/**
+ * Screen key of the currently selected tab.
+ */
 @property (nonatomic, strong, readonly, nonnull) NSString *selectedScreenKey;
 
-/** Monotonically increasing number describing the generation of this state instance.
- *  Used for stale update detection. */
+/**
+ * Monotonically increasing number describing the generation of this state instance.
+ * Used for stale update detection.
+ */
 @property (nonatomic, readonly) int provenance;
 
 - (instancetype)initWithSelectedScreenKey:(nonnull NSString *)selectedScreenKey provenance:(int)provenance;
@@ -76,16 +96,26 @@ typedef NS_ENUM(NSInteger, RNSTabsNavigationStateRejectionReason) {
 
 @end
 
-/** Bundles a navigation state change together with metadata about the selection context. */
+/**
+ * Bundles a navigation state change together with metadata about the selection context.
+ */
 @interface RNSTabsNavigationStateUpdateContext : NSObject
 
-/** The navigation state after the change. */
+/**
+ * The navigation state after the change.
+ */
 @property (nonatomic, readonly, strong, nonnull) RNSTabsNavigationState *navState;
-/** Whether the same tab that was already selected has been selected again. */
+/**
+ * Whether the same tab that was already selected has been selected again.
+ */
 @property (nonatomic, readonly) BOOL isRepeated;
-/** Whether a special effect (e.g. scroll-to-top) was triggered by the selection. */
+/**
+ * Whether a special effect (e.g. scroll-to-top) was triggered by the selection.
+ */
 @property (nonatomic, readonly) BOOL hasTriggeredSpecialEffect;
-/** Origin (actor) that requested this transition. */
+/**
+ * Origin (actor) that requested this transition.
+ */
 @property (nonatomic, readonly) RNSTabsActionOrigin actionOrigin;
 
 - (instancetype)initWithNavState:(nonnull RNSTabsNavigationState *)navState

src/components/tabs/host/TabsHost.types.ts

@@ -67,11 +67,13 @@ export type TabSelectedEvent = {
    * @description
    * - `'user'` — direct native UI interaction (e.g. tab bar tap, iOS tab drag-and-drop).
    * - `'programmatic-js'` — JS-initiated request delivered via the `navStateRequest` prop.
+   * - `'programmatic-native'` — request initiated from the native side by an actor
+   *   integrating directly against the native container.
    * - `'implicit'` — platform side effect not attributable to an explicit actor
    *   (e.g. UIKit reshuffling the selection during a horizontal size-class transition on iPad).
    *   Currently only emitted on iOS.
    */
-  actionOrigin: 'user' | 'programmatic-js' | 'implicit';
+  actionOrigin: 'user' | 'programmatic-js' | 'programmatic-native' | 'implicit';
 };
 
 /**

src/fabric/tabs/TabsHostAndroidNativeComponent.ts

@@ -10,7 +10,7 @@ type TabSelectedEvent = {
   provenance: CT.Int32;
   isRepeated: boolean;
   hasTriggeredSpecialEffect: boolean;
-  actionOrigin: 'user' | 'programmatic-js' | 'implicit';
+  actionOrigin: 'user' | 'programmatic-js' | 'programmatic-native' | 'implicit';
 };
 
 type NavigationStateRequest = {

src/fabric/tabs/TabsHostIOSNativeComponent.ts

@@ -10,7 +10,7 @@ type TabSelectedEvent = Readonly<{
   provenance: CT.Int32;
   isRepeated: boolean;
   hasTriggeredSpecialEffect: boolean;
-  actionOrigin: 'user' | 'programmatic-js' | 'implicit';
+  actionOrigin: 'user' | 'programmatic-js' | 'programmatic-native' | 'implicit';
 }>;
 
 type NavigationStateRequest = Readonly<{