Add verified Joy-Con 2 USB bridge with native mouse support

Implement the standalone USB protocol probe and Bluetooth-backed right Joy-Con bridge with its own persistent virtual pairing identity. Preserve complete ordered native reports, including opaque motion data, and match the console feature set. Relay built-in vibration cues only after genuine source acknowledgement and expose safe BOOTSEL pairing control. Include native capture diagnostics and focused protocol, packet-lifecycle, and cue regressions. Native mouse operation confirmed on Switch with bridge 0.24; private captures and firmware backups remain outside the commit.

tools/switch2_usb_probe/memory.c

@@ -0,0 +1,57 @@
+#include "memory.h"
+#include "probe_memory_data.h"
+#include <string.h>
+
+_Static_assert(sizeof(probe_factory_memory) == 8192, "factory capture size");
+_Static_assert(sizeof(probe_user_calibration) == 4096, "user calibration capture size");
+
+bool probe_memory_read(uint32_t address, uint8_t* output, size_t length) {
+    if (!output) return false;
+    const uint8_t* source;
+    size_t offset, available;
+    if (address >= 0x13000 && address < 0x15000) {
+        offset = address - 0x13000;
+        source = probe_factory_memory;
+        available = sizeof(probe_factory_memory) - offset;
+    } else if (address >= 0x1fc000 && address < 0x1fd000) {
+        offset = address - 0x1fc000;
+        source = probe_user_calibration;
+        available = sizeof(probe_user_calibration) - offset;
+    } else {
+        return false; // No fabricated erased bytes, pairing keys, or firmware reads.
+    }
+    if (length > available) return false;
+    memcpy(output, source + offset, length);
+    return true;
+}
+
+static void unpack_pair(const uint8_t* data, uint16_t values[2]) {
+    values[0] = data[0] | ((uint16_t)(data[1] & 15) << 8);
+    values[1] = (data[1] >> 4) | ((uint16_t)data[2] << 4);
+}
+
+static bool valid_calibration(const uint8_t* data) {
+    uint16_t center[2], positive[2], negative[2];
+    unpack_pair(data, center);
+    unpack_pair(data + 3, positive);
+    unpack_pair(data + 6, negative);
+    // Same bounds as the existing Bluepad32 Switch 2 calibration decoder.
+    for (unsigned i = 0; i < 2; ++i) {
+        if (!center[i] || center[i] == 4095 || !positive[i] || !negative[i] ||
+            positive[i] > 4095 - center[i] || negative[i] > center[i]) return false;
+    }
+    return true;
+}
+
+bool probe_memory_right_stick_center(uint8_t output[3]) {
+    if (!output) return false;
+    // A solo Joy-Con uses the primary calibration record, even for the right
+    // controller. User magic precedes its 9-byte record; factory has no magic.
+    const uint8_t* selected = probe_factory_memory + 0xa8;
+    const uint8_t* user = probe_user_calibration + 0x40;
+    if (user[0] == 0xb2 && user[1] == 0xa1 && valid_calibration(user + 2))
+        selected = user + 2;
+    if (!valid_calibration(selected)) return false;
+    memcpy(output, selected, 3);
+    return true;
+}