identity: shared M3 Expressive theme factory + nav slide spec

FloretExpressiveTheme(lightScheme, darkScheme, darkTheme, dynamicColor,
typography) holds the family's theme mechanics — dynamic-colour resolution
(API 31+), system light/dark fallback, and the STANDARD motion scheme — while
each app supplies its own seed-derived colour schemes, so the look stays
per-app and the machinery is shared. rememberNavSlideSpec() shares the fast
spatial nav slide. android-library, Compose-only.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

identity/build.gradle.kts

@@ -0,0 +1,39 @@
+// identity — the family's Material 3 Expressive theme factory + shared motion.
+// Holds the theme MECHANICS (dynamic-colour resolution, light/dark, the STANDARD
+// motion scheme) and the nav slide spec; each app supplies its own seed-derived
+// colour schemes, so the look stays per-app while the machinery is shared.
+plugins {
+    alias(libs.plugins.android.library)
+    alias(libs.plugins.kotlin.compose)
+}
+
+android {
+    namespace = "de.jeanlucmakiola.floret.identity"
+    compileSdk = 37
+
+    defaultConfig {
+        minSdk = 29
+    }
+
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_17
+        targetCompatibility = JavaVersion.VERSION_17
+    }
+
+    buildFeatures {
+        compose = true
+    }
+}
+
+kotlin {
+    compilerOptions {
+        jvmTarget = org.jetbrains.kotlin.gradle.dsl.JvmTarget.JVM_17
+    }
+}
+
+dependencies {
+    implementation(platform(libs.androidx.compose.bom))
+    implementation(libs.androidx.ui)
+    implementation(libs.androidx.foundation)
+    implementation(libs.androidx.material3)
+}