Exercise fee preset selection through the dropdown UI

Strengthen the send functional regression so it verifies the fee selector's default state, opens the popup, waits for rendered option estimates, and confirms the selected label/duration/index change after choosing Low.

Constraint: The test must validate the user-facing dropdown interaction, not only downstream fee state
Rejected: Rely on selectedTarget alone | insufficient proof that the dropdown path was exercised
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Keep the dropdown assertions aligned with FeeSelection.qml labels and durations if the preset copy changes
Tested: python3 -m py_compile test/functional/qml_test_send_receive.py
Tested: python3 test/functional/qml_test_send_receive.py
Tested: python3 test/functional/qml_test_bridge_sanity.py
Not-tested: Non-low presets beyond asserting their estimates render in the popup

Author: johnny9

test/functional/qml_test_send_receive.py

@@ -16,6 +16,10 @@
 SEND_AMOUNT = "1.00000000"
 GUI_WALLET_NAME = "send_flow_wallet"
 RECEIVER_WALLET_NAME = "send_flow_receiver"
+DEFAULT_FEE_LABEL = "Default"
+DEFAULT_FEE_DURATION = "(~20 mins)"
+LOW_FEE_LABEL = "Low"
+LOW_FEE_DURATION = "(~60 mins)"
 LOW_FEE_OPTION_INDEX = 2
 LOW_FEE_TARGET_BLOCKS = 6
 
@@ -134,11 +138,22 @@ def run_test():
         gui.set_text("sendAmountInput", SEND_AMOUNT)
         gui.wait_for_property("sendContinueButton", "enabled", True, timeout_ms=20000)
 
+        gui.wait_for_property("feeSelectionControl", "selectedLabel", DEFAULT_FEE_LABEL, timeout_ms=5000)
+        gui.wait_for_property("feeSelectionControl", "selectedDuration", DEFAULT_FEE_DURATION, timeout_ms=5000)
+        gui.wait_for_property("feeSelectionControl", "selectedTarget", 2, timeout_ms=5000)
+
         gui.click("feeSelectionDropdownButton")
         gui.wait_for_property("feeSelectionPopup", "opened", True, timeout_ms=5000)
+        high_fee_option_estimate = wait_for_non_empty_text(gui, "feeSelectionOptionEstimate0")
+        default_fee_option_estimate = wait_for_non_empty_text(gui, "feeSelectionOptionEstimate1")
         low_fee_option_estimate = wait_for_non_empty_text(gui, f"feeSelectionOptionEstimate{LOW_FEE_OPTION_INDEX}")
+        assert high_fee_option_estimate, "Expected High option estimate to render in the dropdown"
+        assert default_fee_option_estimate, "Expected Default option estimate to render in the dropdown"
         gui.click(f"feeSelectionOption{LOW_FEE_OPTION_INDEX}")
         gui.wait_for_property("feeSelectionPopup", "opened", False, timeout_ms=5000)
+        gui.wait_for_property("feeSelectionControl", "selectedIndex", LOW_FEE_OPTION_INDEX, timeout_ms=5000)
+        gui.wait_for_property("feeSelectionControl", "selectedLabel", LOW_FEE_LABEL, timeout_ms=5000)
+        gui.wait_for_property("feeSelectionControl", "selectedDuration", LOW_FEE_DURATION, timeout_ms=5000)
         gui.wait_for_property("feeSelectionControl", "selectedTarget", LOW_FEE_TARGET_BLOCKS, timeout_ms=5000)
         gui.wait_for_property("feeSelectionEstimateLabel", "text", low_fee_option_estimate, timeout_ms=20000)