chore(AI): upstream Claude.md (#3930)

Checking into VCS, so that we have a common base to develop.

---------

Co-authored-by: Copilot <[email protected]>

Author: kkafar

.gitignore

@@ -68,7 +68,9 @@ android/.settings
 *Example/artifacts
 
 # AI assistant configuration (local only)
-/CLAUDE.md
-/AGENTS.md
+/CLAUDE.local.md
 /.claude/
 
+# General rule for files explicitly marked as local
+*.local.*
+

AGENTS.md

@@ -0,0 +1,50 @@
+# react-native-screens
+
+This project is a react-native library, focused on exposing native
+navigation containers and implementing common navigation paradigms
+such as stack, tabs, split.
+
+## Repository layout tips
+
+- `./src/` - JS side of the library
+
+  - `./src/components/gamma/` - each directory inside contains JS code for new
+    components, planned for next major release,
+  - `./src/components/safe-area/` - code related to `SafeAreaView` component,
+  - `./src/components/tabs/` - code related to `TabsHost` & `TabsScreen` components,
+
+  - `./src/fabric/` - _codegen_ specs for the components used by the
+    native code generation tool
+
+- `./android/` - Android part of the library implementation,
+- `./ios/` - iOS part of the library implementation,
+- `./cpp/` and `./common/` - C++ layer, shared between Android and iOS parts,
+- `./FabricExample/` - contains an example application, we use it to showcase the library
+  capabilities and test the library. It is not published as part of the package.
+
+- `./apps/` - extracted JS (react-native) code of the `FabricExample` application;
+  this is done to share the code with other example applications in the repository.
+
+- `./react-navigation/` - this is a git submodule for a downstream library providing
+  a complete navigation solution. It is not part of the library.
+
+## Code conventions
+
+- TypeScript-first. Always prefer TypeScript over JavaScript unless explicitly working in a JS-only context.
+- PascalCase for component names, camelCase for hooks (e.g., `useTabsNavigationContext`).
+- Use context hooks when a context exists — do not pass context values as props.
+
+## Imports
+
+- Use relative imports within library packages (`./src/`).
+- Use path aliases (`@apps/*`, `@assets/*`) only in example apps (`./apps/`, `./FabricExample/`).
+- Never use absolute paths from project root as import paths.
+
+## Git & refactoring
+
+- When renaming or deleting across the codebase, always grep for ALL references
+  before committing. Verify zero stale references remain after the change.
+
+## Code review guidelines
+
+Be extremely frank and focused on thoroughness.

CLAUDE.md

@@ -0,0 +1,2 @@
+<!-- Single source of truth lives in AGENTS.md (shared across AI tools) -->
+@AGENTS.md