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

[kkafar]

Description

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.

The recent state/request split (PR #3950) already plumbs actionOrigin from the buffered request through to the emitted event, so adding the variant is mostly additive: union extension on the JS / codegen side, one enum case on each native platform, one switch arm in the iOS conversion helper.

iOS already exposed the surface that downstream needs (RNSTabBarController.setPendingNavigationStateUpdate: is on the public header). On Android, TabsContainer and its pending-op + flush methods were internal, so this PR also widens the Android surface to match: the class is public, the request-passing and flushing methods are public, and the rest stays internal. TabsHost.container stays private — downstream is expected to obtain the container reference through its own integration path, not via the React view.

Stacked on #3950.

Changes

• Public TS TabSelectedEvent.actionOrigin union extended with 'programmatic-native'. Codegen specs (Android + iOS) mirror it.
• iOS: RNSTabsActionOriginProgrammaticNative enum case + matching arm in RNSOnTabSelectedActionOriginFromRNSTabsActionOrigin mapping the Obj-C enum to the codegen C++ scoped enum.
• Android: TabsActionOrigin.PROGRAMMATIC_NATIVE + toString() mapping.
• Android visibility widening:
  • TabsContainer class is now public; constructor stays internal (it takes the still-internal TabsContainerDelegate).
  • setContainerOperation(TabsContainerOp) replaced with public setPendingNavigationStateUpdate(TabsNavStateUpdateRequest) — takes the request directly, wraps in TabSelectOp internally. Naming mirrors the iOS selector.
  • performContainerUpdateIfNeeded() is public — the flush trigger.
  • TabsContainerOp / TabSelectOp stay internal.
• iOS doc comments in RNSTabsNavigationState.h reformatted: per-case /** … */ blocks for RNSTabsActionOrigin (and the rest of the file made consistent with /**\n * …\n */ style).

Test plan

• yarn check-types clean.
• yarn lint clean for changed files (only pre-existing warnings in unrelated code).
• yarn android from FabricExample/ — Android codegen + Kotlin compile clean. App installs on emulator.
• Grep sweep:
  • git grep -n "programmatic-native" -- src/ → 3 hits (public TS type + both codegen specs).
  • git grep -n "RNSTabsActionOriginProgrammaticNative" -- ios/ → hits in RNSTabsNavigationState.h and RNSConversions-Tabs.mm.
  • git grep -n "PROGRAMMATIC_NATIVE" -- android/ → hits in TabsActionOrigin.kt.
  • git grep -n "setContainerOperation" -- android/ → zero hits (renamed).
  • git grep -nE "internal class TabsContainer\b" -- android/ → zero hits (class made public).
• iOS Xcode build via bundle exec pod install && yarn ios (regenerates iOS codegen with the extended union) — pending local Mac toolchain run.
• Runtime smoke from a downstream consumer producing programmatic-native is out of scope — this library has no producer call site.

Checklist

• Included code example that can be used to test this change.
• For visual changes, included screenshots / GIFs / recordings documenting the change.
• For API changes, updated relevant public types.
• Ensured that CI passes

[Copilot]

Pull request overview

Extends the public TabSelectedEvent.actionOrigin API to include a new 'programmatic-native' variant, enabling downstream native integrations to attribute tab changes initiated directly by native container/controller APIs.

Changes:

• Extend the JS/TS and codegen event contract to include 'programmatic-native' for actionOrigin.
• iOS: add RNSTabsActionOriginProgrammaticNative and map it to the codegen event enum in RNSConversions-Tabs.mm; reformat doc comments in RNSTabsNavigationState.h.
• Android: add TabsActionOrigin.PROGRAMMATIC_NATIVE, and widen TabsContainer visibility plus expose public methods to set/flush pending navigation state updates.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/fabric/tabs/TabsHostIOSNativeComponent.ts	Extends codegen event union with 'programmatic-native'.
src/fabric/tabs/TabsHostAndroidNativeComponent.ts	Extends codegen event union with 'programmatic-native'.
src/components/tabs/host/TabsHost.types.ts	Extends public TS actionOrigin union and docs.
ios/tabs/host/RNSTabsNavigationState.h	Adds iOS enum case and reformats doc comments.
ios/conversion/RNSConversions-Tabs.mm	Maps Obj-C action origin enum to codegen event enum, adding native-programmatic arm.
android/src/main/java/com/swmansion/rnscreens/gamma/tabs/host/TabsHost.kt	Updates host to use new TabsContainer API for pending updates.
android/src/main/java/com/swmansion/rnscreens/gamma/tabs/container/TabsContainer.kt	Makes container public and exposes pending-update + flush entrypoints.
android/src/main/java/com/swmansion/rnscreens/gamma/tabs/container/TabsActionOrigin.kt	Adds PROGRAMMATIC_NATIVE and string mapping.

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[kligarski]

For iOS, what is the intended flow for programmatic native operation?

Is it setPendingNavigationStateUpdate and then updateSelectedViewControllerIfNeeded? But this way we're missing setting _isHandlingExplicitSelectionUpdate flag which is done in performContainerUpdate and performContainerUpdate is not public.

Currently, if we use updateSelectedViewControllerIfNeeded, reconcileNavigationStateWithUIKitState is called (because we're not setting _isHandlingExplicitSelectionUpdate). Fortunately, we're early-returning via [_navigationState.selectedScreenKey isEqualToString:selectedScreenKey] check but I'm not sure if this was intended?

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I also thought whether we should allow anyone to use setPendingNavigationStateUpdate and set any actionOrigin or maybe only expose a method that will accept only the key (and baseProvenance?) that will enforce ProgrammaticNative origin.