ios: smooth Agent entrances and refresh app icon

Grow row height and spacing with the existing entrance animation, remove the Latest overlay while retaining scroll/read/send behavior, and reuse the current PWA icon artwork. Cover occupied-height interpolation and scroll-to-latest navigation in focused checks.

ios/Tests/SybilUITests/AgentUITests.swift

@@ -313,7 +313,8 @@ final class AgentUITests: XCTestCase {
         XCTAssertTrue(app.staticTexts["History message 160: local simulator fixture."].isHittable)
         scroll.swipeDown()
         scroll.swipeDown()
-        XCTAssertTrue(app.buttons["agent-jump-latest"].waitForExistence(timeout: 3))
+        XCTAssertFalse(app.staticTexts["History message 160: local simulator fixture."].isHittable)
+        XCTAssertFalse(app.buttons["agent-jump-latest"].exists)
         let anchor = try XCTUnwrap(app.staticTexts.matching(NSPredicate(format: "label BEGINSWITH %@", "History message")).allElementsBoundByIndex.first { $0.isHittable })
         let before = anchor.frame.minY
         try await control(["action": "reply", "content": "Reply while reading earlier history"])
@@ -327,14 +328,27 @@ final class AgentUITests: XCTestCase {
         XCTAssertTrue(app.buttons["Load earlier messages"].isHittable)
         app.buttons["Load earlier messages"].tap()
         // Loading older lazy history may move the viewport. It must still load
-        // the remaining history and preserve Latest/keyboard behavior below.
+        // the remaining history and preserve scroll-to-latest/keyboard behavior below.
         XCTAssertFalse(app.buttons["Load earlier messages"].exists)
         capture("agent-older-history-loaded")
-        app.buttons["agent-jump-latest"].tap()
-        XCTAssertTrue(app.staticTexts["Reply while reading earlier history"].isHittable)
+        let latest = app.staticTexts["Reply while reading earlier history"]
+        for _ in 0..<30 {
+            if latest.isHittable { break }
+            scroll.swipeUp(velocity: .fast)
+        }
+        scroll.swipeUp(velocity: .slow)
+        XCTAssertTrue(latest.isHittable)
         composer.tap(); composer.typeText("A multiline draft\nwith a second line\nand a third line")
         XCTAssertTrue(app.staticTexts["Reply while reading earlier history"].isHittable)
         capture("agent-multiline-keyboard")
+        // Sending remains the explicit navigation path while reading history.
+        scroll.swipeDown(velocity: .slow)
+        scroll.swipeDown(velocity: .slow)
+        XCTAssertFalse(latest.isHittable)
+        app.buttons["agent-send"].tap()
+        let sent = app.staticTexts["A multiline draft\nwith a second line\nand a third line"]
+        let followed = XCTNSPredicateExpectation(predicate: NSPredicate(format: "hittable == true"), object: sent)
+        await fulfillment(of: [followed], timeout: 5)
     }
 
     func testBackgroundUnreadReadReconciliationAndReplay() async throws {