Sprint 1 complete: hybrid Compose + LibGDX architecture building

Full AL-001 through AL-008 implementation: shared/ module with ModuleType
enum, GameHost routing, StylusInputBridge, LineCorridorScreen with live
stroke rendering, LineScore (straightness + anglePrecision), score returned
to Compose hub via ActivityResult. Fixes LineScore field mismatch
(pressureConsistency → anglePrecision) caught during AL-009 build check.
Adds .gitignore and handoff notes.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

core/build.gradle.kts

@@ -6,6 +6,7 @@ val gdxVersion: String by project
 
 dependencies {
     api("com.badlogicgames.gdx:gdx:$gdxVersion")
+    implementation(project(":shared"))
 }
 
 kotlin {