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/tests/BrowserSecurityTest.kt

@@ -0,0 +1,66 @@
+package community.yuvomi.mobile
+
+import android.content.Context
+import android.net.Uri
+import android.view.View
+import android.view.ViewGroup
+import android.webkit.WebResourceRequest
+import android.webkit.WebView
+import androidx.test.core.app.ActivityScenario
+import androidx.test.core.app.ApplicationProvider
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertNotNull
+import org.junit.Assert.assertNull
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@RunWith(AndroidJUnit4::class)
+class BrowserSecurityTest {
+    @Test fun blocksCrossOriginPostAndSubresourceBeforeNetwork() {
+        val context = ApplicationProvider.getApplicationContext<Context>()
+        context.getSharedPreferences("server", Context.MODE_PRIVATE).edit()
+            .putString("origin", "https://family.example").commit()
+        ActivityScenario.launch(MainActivity::class.java).use { scenario ->
+            lateinit var web: WebView
+            lateinit var client: android.webkit.WebViewClient
+            scenario.onActivity {
+                web = requireNotNull(findWeb(it.window.decorView))
+                client = web.webViewClient
+            }
+            // Interception runs off the UI thread in WebView. POST navigations do
+            // not reliably call shouldOverrideUrlLoading, so this is a separate gate.
+            for (mainFrame in listOf(true, false)) {
+                val response = client.shouldInterceptRequest(
+                    web,
+                    Request("https://evil.example/collect", mainFrame),
+                )
+                assertNotNull(response)
+                assertEquals(403, response!!.statusCode)
+            }
+            assertNull(
+                client.shouldInterceptRequest(web, Request("https://family.example/tasks", true)),
+            )
+        }
+    }
+
+    private fun findWeb(view: View): WebView? {
+        if (view is WebView) return view
+        if (view is ViewGroup) {
+            for (i in 0 until view.childCount) {
+                findWeb(view.getChildAt(i))?.let {
+                    return it
+                }
+            }
+        }
+        return null
+    }
+    private class Request(private val value: String, private val mainFrame: Boolean) : WebResourceRequest {
+        override fun getUrl(): Uri = Uri.parse(value)
+        override fun isForMainFrame() = mainFrame
+        override fun isRedirect() = false
+        override fun hasGesture() = true
+        override fun getMethod() = "POST"
+        override fun getRequestHeaders(): MutableMap<String, String> = mutableMapOf()
+    }
+}