feat(android): replace WebView with tested native Compose API slice

Add real native onboarding/auth/dashboard/tasks/notes/shopping, origin-bound HTTPS and encrypted AndroidKeyStore session persistence. Archive the superseded browser renderer and tests. Verify 10 JVM tests, 6 native API-35 emulator tests, lintDebug/lintRelease and debug/unsigned release APK/AAB builds; the real upstream suite passes 7 tests and exports a nonblank native fixture screenshot. Tink host-tool update removes the old generated-protobuf warning. Full module/visual parity remains explicitly incomplete.

legacy/android/SelectionGateTest.kt

@@ -0,0 +1,31 @@
+package community.yuvomi.mobile
+
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class SelectionGateTest {
+    @Test fun acceptsOnlyTheInitiatingContextOnce() {
+        val gate = SelectionGate()
+        assertTrue(gate.begin(0))
+        assertTrue(gate.consume(0))
+        assertFalse(gate.consume(0))
+    }
+
+    @Test fun serverSwitchCannotDeliverAnOldSelectionToTheNewServer() {
+        val gate = SelectionGate()
+        assertTrue(gate.begin(0))
+        assertFalse(gate.begin(1))
+        assertFalse(gate.consume(1))
+        assertTrue(gate.begin(1))
+        assertTrue(gate.consume(1))
+    }
+
+    @Test fun processRecreationCancelsSelectionWithoutReusingItsCallback() {
+        val gate = SelectionGate()
+        gate.restoreOutstanding()
+        assertFalse(gate.begin(0))
+        assertFalse(gate.consume(0))
+        assertTrue(gate.begin(0))
+    }
+}