Add AGENTS.md for AI coding agent guidance

- Create AGENTS.md with project overview, build commands, architecture,
  and key technology choices for AI coding agents
- Symlink CLAUDE.md -> AGENTS.md so Claude Code picks up the same content
- Add .claude to .gitignore

.gitignore

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 # Kotlin
 .kotlin
+
+# Claude Code
+.claude

AGENTS.md

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+# AGENTS.md
+
+This file provides guidance to AI coding agents when working with code in this repository.
+
+## Project Overview
+
+Now in Android (KMP edition) — a Kotlin Multiplatform fork of Google's Now in Android reference app. Targets Android, iOS, Desktop (JVM), macOS, and experimental Web (WASM). Uses Compose Multiplatform for shared UI.
+
+## Build Commands
+
+```bash
+# Format code (must pass before merge)
+./gradlew spotlessApply
+./gradlew spotlessCheck --init-script gradle/init.gradle.kts --no-configuration-cache
+
+# Build
+./gradlew :app:assemble                     # main app (all variants)
+./gradlew :app-nia-catalog:assemble          # design system catalog app
+
+# Run desktop app
+# Gradle run config task: desktopRun -DmainClass=MainKt --quiet
+
+# Unit tests (only demoDebug variant has test coverage)
+./gradlew testDemoDebug                      # all module tests
+./gradlew :feature:foryou:testDemoDebug      # single module test
+./gradlew :lint:test                         # lint rule tests
+
+# Instrumented tests (requires a connected Android emulator)
+./gradlew connectedDemoDebugAndroidTest
+
+# Screenshot tests (Roborazzi — CI only, do NOT run locally)
+# CI records/verifies screenshots and auto-commits updates via PR
+# ./gradlew verifyRoborazziDemoDebug         # verify against baselines (CI only)
+# ./gradlew recordRoborazziDemoDebug         # record new baselines (CI only)
+
+# Lint
+./gradlew :app:lintProdRelease :app-nia-catalog:lintRelease :lint:lint
+
+# Dependency guard
+./gradlew dependencyGuard                    # check
+./gradlew dependencyGuardBaseline            # update baseline
+
+# Build-logic check
+./gradlew :build-logic:convention:check
+
+# Badging check
+./gradlew :app:checkProdReleaseBadging
+```
+
+## Architecture
+
+**Three-layer architecture** with unidirectional data flow (UDF):
+- **UI Layer** (`feature:*`) — Compose screens + ViewModels. Each feature module is independent; no inter-feature dependencies.
+- **Domain Layer** (`core:domain`) — Use cases combining data from multiple repositories.
+- **Data Layer** (`core:data`, `core:database`, `core:datastore`, `core:network`) — Offline-first repositories backed by SQLDelight + Proto DataStore, synced via Ktor/Ktrofit.
+
+### Module Structure
+
+- **`app`** — Main KMP application with app-level navigation (NiaNavHost, TopLevelDestination). WIP for full multiplatform.
+- **`app-nia-catalog`** — Standalone design system showcase. Fully multiplatform including WASM.
+- **`feature:*`** — Feature modules (foryou, interests, bookmarks, topic, search, settings). Depend only on `core:*` modules.
+- **`core:*`** — Shared libraries. Key ones: `designsystem` (Material 3 components), `ui` (reusable composables), `model` (data types), `data` (repositories), `database` (SQLDelight), `network` (Ktor), `datastore` (Proto DataStore).
+- **`shared`** — Aggregates features and core for the main app.
+- **`sync:work`** — WorkManager-based sync (Android-only).
+- **`build-logic/convention`** — Custom Gradle convention plugins.
+
+### Convention Plugins
+
+All modules use convention plugins from `build-logic/convention/` (plugin IDs prefixed `nowinandroid.*`):
+- `nowinandroid.kmp.library` — KMP library: configures Android library + KMP targets (JVM, Android, iOS, macOS) + common test deps
+- `nowinandroid.cmp.application` — Compose Multiplatform app (Android, Desktop, iOS, macOS)
+- `nowinandroid.cmp.feature` — Feature module (inherits kmp.library + adds Compose, Koin, core:ui, core:designsystem)
+- `nowinandroid.di.koin` — Koin DI with KSP annotation processing
+- `nowinandroid.sqldelight` — SQLDelight database
+- `nowinandroid.kmp.inject` — kotlin-inject DI via KSP
+
+### Key Technology Choices
+
+- **DI:** Koin (primary, KMP-friendly service locator) + kotlin-inject (compile-time alternative)
+- **Database:** SQLDelight (multiplatform)
+- **Preferences:** Proto DataStore
+- **Networking:** Ktor client via Ktrofit
+- **Image loading:** Coil 3
+- **Serialization:** kotlinx-serialization
+- **Testing:** No mocking libraries — use test doubles. Roborazzi for screenshot tests (CI only), Turbine for Flow testing.
+
+### Build Variants
+
+Two flavor dimensions: `demo` (local static data) and `prod` (requires backend server, not public). Use `demoDebug` for development.
+
+### KMP Source Set Layout
+
+Modules use Kotlin Multiplatform default hierarchy: `commonMain`/`commonTest`, `androidMain`/`androidUnitTest`/`androidInstrumentedTest`, `jvmMain`/`jvmTest`, `iosMain`, `macosMain`, etc. Android resource prefixes are auto-derived from module path (e.g., `core_model_`).
+
+## Requirements
+
+- JDK 17+
+- Gradle uses 4GB heap (`-Xmx4g`)
+- Configuration cache and parallel builds enabled

CLAUDE.md

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+AGENTS.md