feat(hierarchy): flat-to-tree + path query selector (#41)

* feat(hierarchy): add Node tree + path query support

Preserve parent-child relationships in a Node tree at parse time.
Extend Find/FindAll with " > " path operator for scoped queries,
e.g. id:LoginScreen > desc:EmailInput.

Flat Elements slice and all public signatures unchanged.

* test(hierarchy): add path query tests

Cover single-level, multi-level, mixed-type, not-found, wrong-subtree,
and FindAll across multiple roots.

* feat(folio): add modifier param to Screen composable

* feat(folio): testTag LoginScreen

* feat(folio): testTag HomeScreen

* feat(folio): testTag AddAccountScreen

* feat(folio): testTag LedgerScreen

* feat(folio): testTag AddTransactionScreen

* feat(folio): scope spec selectors to screen testTags via path queries

* fix(sidecar): align grpc-netty/grpc-okhttp with grpc-core version

Maestro 1.40.0 brings grpc-netty:1.50.2 which compiled against
AbstractManagedChannelImplBuilder, removed in grpc-core 1.64+.
Gradle was upgrading grpc-core to 1.68.0 while leaving grpc-netty at
1.50.2, causing NoClassDefFoundError at startup.

Force grpc-netty and grpc-okhttp to match grpcVersion so all gRPC
artifacts are binary-compatible.

* fix(sidecar): use ephemeral host port for AndroidDriver

Hard-coded port 7001 caused TcpForwarder.start() to fail with
TimeoutException when a previous sidecar process held the port open.
Pick a free port via ServerSocket(0) instead.

* chore(sidecar): bump maestro to 2.4.0, exclude graalvm from fat JAR

Maestro 2.4.0 still ships grpc-netty:1.50.2 so the grpc transport
resolution strategy is kept. GraalVM JS is excluded: unused by our
sidecar and causes shadow JAR expansion errors (pom treated as zip).

* fix(sidecar): update AndroidDriver calls for Maestro 2.4.0 API

launchApp no longer accepts a UUID argument. Third constructor param
changed from hostname to emulatorName so drop the "localhost" value.

sidecar/build.gradle.kts

@@ -21,7 +21,25 @@ kotlin {
 
 val grpcVersion = "1.68.0"
 val protobufVersion = "3.25.5"
-val maestroVersion = "1.40.0"
+val maestroVersion = "2.4.0"
+
+// Maestro 2.4.0 still declares grpc-netty:1.50.2 and grpc-okhttp:1.50.2 which
+// were compiled against AbstractManagedChannelImplBuilder removed in grpc-core 1.64+.
+// Force them to the version we pin so they stay binary-compatible.
+// Also exclude GraalVM JS — not used by our sidecar and causes shadow JAR expansion errors.
+configurations.all {
+    resolutionStrategy.eachDependency {
+        if (requested.group == "io.grpc" &&
+            (requested.name == "grpc-netty" || requested.name == "grpc-okhttp")) {
+            useVersion(grpcVersion)
+            because("align grpc transport with grpc-core version")
+        }
+    }
+    exclude(group = "org.graalvm.js")
+    exclude(group = "org.graalvm.sdk")
+    exclude(group = "org.graalvm.regex")
+    exclude(group = "org.graalvm.truffle")
+}
 
 dependencies {
     implementation("dev.mobile:maestro-client:$maestroVersion")
@@ -81,6 +99,7 @@ application {
 // depend on `version`.
 tasks.named<com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar>("shadowJar") {
     archiveFileName.set("sidecar-all.jar")
+    exclude("META-INF/*.SF", "META-INF/*.DSA", "META-INF/*.RSA")
 }
 
 // JUnit 4 (vintage) for the gRPC GrpcCleanupRule + JUnit 5 (jupiter)