fix: Don't notify about a reaction sent by a blocked contact (#8729)

Fixes https://github.com/chatmail/core/issues/8692: Now the user does
not get notifications when a blocked contact reacts to some message.

What this PR does not change is what happens when being in a group with
a blocked contact; it only fixes this obvious bug.

I checked that the test fails without the fix.

src/receive_imf.rs

@@ -2107,7 +2107,8 @@ async fn add_parts(
         let hidden = part.is_reaction;
         if part.is_reaction {
             let reaction_str = simplify::remove_footers(part.msg.as_str());
-            let is_incoming_fresh = mime_parser.incoming && !seen;
+            let is_incoming_fresh =
+                mime_parser.incoming && !seen && chat_id_blocked == Blocked::Not;
             set_msg_reaction(
                 context,
                 mime_in_reply_to,

src/receive_imf/receive_imf_tests.rs

@@ -3364,6 +3364,35 @@ async fn test_blocked_contact_creates_group() -> Result<()> {
     Ok(())
 }
 
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn test_blocked_contact_sends_reaction() -> Result<()> {
+    let mut tcm = TestContextManager::new();
+    let alice = &tcm.alice().await;
+    let bob = &tcm.bob().await;
+
+    let bob_msg_id = tcm.send_recv_accept(alice, bob, "Hi!").await.id;
+
+    let chat = alice.get_chat(bob).await;
+    chat.id.block(alice).await?;
+
+    crate::reaction::send_reaction(bob, bob_msg_id, "👍").await?;
+    let sent = bob.pop_sent_msg().await;
+    alice.recv_msg_hidden(&sent).await;
+    alice.emit_event(EventType::Test);
+
+    while let Some(ev) = alice.evtracker.recv().await {
+        match ev.typ {
+            EventType::IncomingReaction { .. } => {
+                panic!("Alice is not supposed to receive a notification, since she blocked Bob")
+            }
+            EventType::Test => break,
+            _ => {}
+        }
+    }
+
+    Ok(())
+}
+
 #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
 async fn test_outgoing_undecryptable() -> Result<()> {
     let alice = &TestContext::new().await;