feat(gdma): expose interrupt priority as a configurable option

- Add intr_priority field to gdma_channel_t structure
- Add intr_bind_name field to gdma_signal_conn_t for interrupt binding
- Validate intr_priority during channel allocation (must be 0-3)
- Use ESP_INTR_FLAG_SHARED_PRIVATE instead of ESP_INTR_FLAG_SHARED
- Use esp_intr_alloc_info() with bind_by.name for shared interrupts
- Add interrupt priority configuration test case
- Update all gdma_periph.c files with pair-specific bind names (gdma_gXpY)

components/esp_hal_dma/include/hal/gdma_periph.h

@@ -31,13 +31,16 @@ extern "C" {
 #endif
 
 #if SOC_HAS(GDMA)
+typedef struct {
+    const int rx_irq_id;
+    const int tx_irq_id;
+    const char *name; // pair name, format: "gdma_gXpY"
+} gdma_pair_signal_conn_t;
+
 typedef struct {
     struct {
         const shared_periph_module_t module;
-        struct {
-            const int rx_irq_id;
-            const int tx_irq_id;
-        } pairs[GDMA_LL_GET(PAIRS_PER_INST)];
+        gdma_pair_signal_conn_t pairs[GDMA_LL_GET(PAIRS_PER_INST)];
     } groups[GDMA_LL_GET(INST_NUM)];
 } gdma_signal_conn_t;