Update test fixtures to current runtime contracts (#14259)

Recent runtime changes left the aggregate suite expecting a VS Code symlink and fixed extension version, pacman arguments without the end-of-options marker, a one-argument QML text signal, and background functions without preparation state. Align these fixtures with the current interfaces while retaining palette equality, package retry, keyboard action, and missing-background recovery assertions.

Co-authored-by: Omarchybot <317366263+omarchybot@users.noreply.github.com>

test/shell.d/fixtures/network-captive-portal/shell.qml

@@ -68,7 +68,7 @@ ShellRoot {
     var before = NetworkMock.checks
     panel.testPoll.triggered()
     check(NetworkMock.checks === before + 1, "background timer rechecks through NM")
-    panel.testKeys.textKey("r")
+    panel.testKeys.textKey("r", Qt.NoModifier)
     check(NetworkMock.checks === before + 2, "r requests fresh connectivity")
     // Exercise the existing cursor model, not a separate test-only action.
     panel.cursorActive = true