Extract HID report size for EDBG debug tools via HID endpoint descriptor.

Removed hidapi bodge (where we were mimicking the hid_device_ struct, to
obtain the report size via `(hid_device_*)->input_ep_max_packet_size`).

src/DebugToolDrivers/Microchip/EdbgDevice.cpp

@@ -30,14 +30,19 @@ namespace Bloom::DebugToolDrivers
     void EdbgDevice::init() {
         UsbDevice::init();
 
-        auto cmsisHidInterface = Usb::HidInterface(this->cmsisHidInterfaceNumber, this->vendorId, this->productId);
-
-        this->detachKernelDriverFromInterface(cmsisHidInterface.interfaceNumber);
+        this->detachKernelDriverFromInterface(this->cmsisHidInterfaceNumber);
 
         if (this->configurationIndex.has_value()) {
             this->setConfiguration(this->configurationIndex.value());
         }
 
+        auto cmsisHidInterface = Usb::HidInterface(
+            this->cmsisHidInterfaceNumber,
+            this->getCmsisHidReportSize(),
+            this->vendorId,
+            this->productId
+        );
+
         cmsisHidInterface.init();
 
         this->edbgInterface = std::make_unique<EdbgInterface>(std::move(cmsisHidInterface));
@@ -125,4 +130,33 @@ namespace Bloom::DebugToolDrivers
 
         this->sessionStarted = false;
     }
+
+    std::uint16_t EdbgDevice::getCmsisHidReportSize() {
+        const auto activeConfigDescriptor = this->getConfigDescriptor();
+
+        for (auto interfaceIndex = 0; interfaceIndex < activeConfigDescriptor->bNumInterfaces; ++interfaceIndex) {
+            const auto* interfaceDescriptor = (activeConfigDescriptor->interface + interfaceIndex)->altsetting;
+
+            if (interfaceDescriptor->bInterfaceNumber != this->cmsisHidInterfaceNumber) {
+                continue;
+            }
+
+            for (auto endpointIndex = 0; endpointIndex < activeConfigDescriptor->bNumInterfaces; ++endpointIndex) {
+                const auto* endpointDescriptor = (interfaceDescriptor->endpoint + endpointIndex);
+
+                if ((endpointDescriptor->bEndpointAddress & LIBUSB_ENDPOINT_DIR_MASK) != LIBUSB_ENDPOINT_IN) {
+                    // Not an IN endpoint
+                    continue;
+                }
+
+                return endpointDescriptor->wMaxPacketSize;
+            }
+        }
+
+        throw DeviceInitializationFailure(
+            "Failed to obtain CMSIS-DAP HID report size via endpoint descriptor - could not find IN endpoint for "
+            "selected configuration value (" + std::to_string(activeConfigDescriptor->bConfigurationValue)
+            + ") and interface number (" + std::to_string(this->cmsisHidInterfaceNumber) + ")"
+        );
+    }
 }