chore: add gradle wrapper + version catalog + root build

Bootstrapped Gradle 8.14 wrapper from HouseHoldKeaper, then upgraded
to 9.5.1 (required by AGP 9.1.1). All dependency versions verified as
latest stable on 2026-06-08, with Material 3 deliberately pinned to
1.5.0-alpha21 (Expressive APIs are not in any stable release yet).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

settings.gradle.kts

@@ -0,0 +1,24 @@
+pluginManagement {
+    repositories {
+        google {
+            content {
+                includeGroupByRegex("com\\.android.*")
+                includeGroupByRegex("com\\.google.*")
+                includeGroupByRegex("androidx.*")
+            }
+        }
+        mavenCentral()
+        gradlePluginPortal()
+    }
+}
+
+dependencyResolutionManagement {
+    repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS)
+    repositories {
+        google()
+        mavenCentral()
+    }
+}
+
+rootProject.name = "Calendula"
+include(":app")