Add personal notes, DeepSearch history, backup offload, and gateway auth throttling

Also streamline the top navigation: drop the Tools dropdown, make Quizzes
and Battles icon-only entries, and remove the Workspace, Containers and
Editor entry points from the project detail page.

tests/e2e/messages.py

@@ -406,3 +406,120 @@ def test_live_incoming_message_shows_report_button(alice, bob):
     bubble = page_b.locator(f".message-bubble.theirs:has-text('{msg}')")
     bubble.wait_for(state="visible", timeout=10000)
     expect(bubble.locator(".message-report-btn")).to_be_visible()
+
+
+def test_send_button_locks_during_send_and_prevents_duplicate(alice, bob):
+    page_a, user_a = alice
+    page_b, user_b = bob
+    uid_b = get_table("users").find_one(username=user_b["username"])["uid"]
+
+    page_a.goto(
+        f"{BASE_URL}/messages?with_uid={uid_b}", wait_until="domcontentloaded"
+    )
+
+    msg = f"Locked send {int(time.time() * 1000)}"
+    textarea = page_a.locator(".messages-input-area textarea[name='content']")
+    textarea.wait_for(state="visible")
+    textarea.fill(msg)
+
+    send_btn = page_a.locator(".messages-send-btn")
+    send_btn.click()
+
+    # the composer refuses a duplicate submit while this send is unconfirmed
+    expect(send_btn).to_be_disabled()
+
+    bubble = page_a.locator(f".message-bubble.mine:has-text('{msg}')")
+    reconciled = page_a.locator(
+        f".message-bubble.mine:has-text('{msg}')[data-msg-uid]:not(.pending)"
+    )
+    reconciled.first.wait_for(state="visible", timeout=10000)
+
+    expect(send_btn).to_be_enabled()
+    assert bubble.count() == 1
+
+
+def test_scroll_up_is_not_yanked_by_incoming_message(alice, bob):
+    from datetime import datetime, timedelta, timezone
+    from devplacepy.utils import generate_uid
+
+    page_a, user_a = alice
+    page_b, user_b = bob
+    uid_a = get_table("users").find_one(username=user_a["username"])["uid"]
+    uid_b = get_table("users").find_one(username=user_b["username"])["uid"]
+
+    base = datetime.now(timezone.utc) - timedelta(minutes=5)
+    for i in range(40):
+        get_table("messages").insert(
+            {
+                "uid": generate_uid(),
+                "sender_uid": uid_a if i % 2 == 0 else uid_b,
+                "receiver_uid": uid_b if i % 2 == 0 else uid_a,
+                "content": f"scroll history line {i}",
+                "read": True,
+                "created_at": (base + timedelta(seconds=i)).isoformat(),
+                "updated_at": None,
+            }
+        )
+
+    page_a.goto(
+        f"{BASE_URL}/messages?with_uid={uid_b}", wait_until="domcontentloaded"
+    )
+    page_b.goto(
+        f"{BASE_URL}/messages?with_uid={uid_a}", wait_until="domcontentloaded"
+    )
+
+    thread = page_a.locator(".messages-thread")
+    thread.wait_for(state="visible")
+    thread.locator(".message-bubble").first.wait_for(state="visible")
+
+    thread.evaluate(
+        "el => { el.scrollTop = 0; el.dispatchEvent(new Event('scroll')); }"
+    )
+    page_a.wait_for_timeout(200)
+    scroll_before = thread.evaluate("el => el.scrollTop")
+    assert scroll_before < 50
+
+    msg = f"While scrolled up {int(time.time() * 1000)}"
+    textarea_b = page_b.locator(".messages-input-area textarea[name='content']")
+    textarea_b.wait_for(state="visible")
+    textarea_b.fill(msg)
+    page_b.locator(".messages-send-btn").click()
+
+    page_a.locator(f".message-bubble.theirs:has-text('{msg}')").first.wait_for(
+        state="visible", timeout=10000
+    )
+    scroll_after = thread.evaluate("el => el.scrollTop")
+    assert scroll_after < 50, (
+        "an incoming message must not yank a scrolled-up reader back to the bottom"
+    )
+
+
+def test_scroll_stays_pinned_to_bottom_for_active_reader(alice, bob):
+    page_a, user_a = alice
+    page_b, user_b = bob
+    uid_a = get_table("users").find_one(username=user_a["username"])["uid"]
+    uid_b = get_table("users").find_one(username=user_b["username"])["uid"]
+
+    page_a.goto(
+        f"{BASE_URL}/messages?with_uid={uid_b}", wait_until="domcontentloaded"
+    )
+    page_b.goto(
+        f"{BASE_URL}/messages?with_uid={uid_a}", wait_until="domcontentloaded"
+    )
+
+    thread = page_a.locator(".messages-thread")
+    thread.wait_for(state="visible")
+
+    msg = f"Pinned bottom {int(time.time() * 1000)}"
+    textarea_b = page_b.locator(".messages-input-area textarea[name='content']")
+    textarea_b.wait_for(state="visible")
+    textarea_b.fill(msg)
+    page_b.locator(".messages-send-btn").click()
+
+    page_a.locator(f".message-bubble.theirs:has-text('{msg}')").first.wait_for(
+        state="visible", timeout=10000
+    )
+    at_bottom = thread.evaluate(
+        "el => el.scrollHeight - el.scrollTop - el.clientHeight < 100"
+    )
+    assert at_bottom, "an active-at-bottom reader must still auto-scroll to new messages"