Testing: split input test (#2762)

test(pointing): Add mock input device.

New mock input device to generate input events for tests.

test(split): Add peripheral input test.

Test event propagation from peripheral input devices.

fix(split): Proper scoping for local within switch.

Minor compile fix.

chore: Fix up test snapshots after logging changes.

Adjust the test snapshots after logging changes to the central.

fix(kscan): Don't fire last mock event twice.

Fix a bug where the kscan mock would raise the last mock event
twice before halting processing.

app/module/drivers/kscan/kscan_mock.c

@@ -65,6 +65,12 @@ static int kscan_mock_configure(const struct device *dev, kscan_callback_t callb
         struct k_work_delayable *d_work = k_work_delayable_from_work(work);                        \
         struct kscan_mock_data *data = CONTAINER_OF(d_work, struct kscan_mock_data, work);         \
         const struct kscan_mock_config_##n *cfg = data->dev->config;                               \
+        if (data->event_index >= DT_INST_PROP_LEN(n, events)) {                                    \
+            if (cfg->exit_after)                                                                   \
+                exit(0);                                                                           \
+            else                                                                                   \
+                return;                                                                            \
+        }                                                                                          \
         uint32_t ev = cfg->events[data->event_index];                                              \
         LOG_DBG("ev %u row %d column %d state %d\n", ev, ZMK_MOCK_ROW(ev), ZMK_MOCK_COL(ev),       \
                 ZMK_MOCK_IS_PRESS(ev));                                                            \