feat(ble/bluedroid): Support bluedroid dual identity

(cherry picked from commit 2358786647)

Co-authored-by: zhiweijian <zhiweijian@espressif.com>

docs/en/api-guides/ble/bluedroid-dual-identity-host-dev.rst

@@ -0,0 +1,25 @@
+Bluedroid Host Support for Dual Local Identities
+================================================
+
+:link_to_translation:`zh_CN:[中文]`
+
+Introduction
+------------
+
+When a single peer phone connects to an ESP32 peripheral through two different **local identities** (for example, a Public address and a fixed Static Random address from two extended advertising sets), the default Bluedroid Host treats both links as the same peer. Bonds, LTK, and NVS sections can overwrite each other.
+
+Enable :ref:`BT_BLE_PERIPH_PSEUDO_ADDR_BOND <CONFIG_BT_BLE_PERIPH_PSEUDO_ADDR_BOND>` to derive a Host-internal **pseudo address** ``f(local_identity, peer)`` per link. The application sees two different ``remote_bda`` values for the same phone, while SMP and the controller still use the real peer identity on air.
+
+Example
+-------
+
+See :example:`ble50_dual_identity_server <bluetooth/bluedroid/ble_50/ble50_dual_identity_server>` for a Bluetooth LE 5.0 peripheral that advertises two identities concurrently, pairs with both, and keeps **isolated bonds per (local, peer) pair**.
+
+Application Notes
+-----------------
+
+- Use **conn_id** as the link key in GATTS calls; do not use ``remote_bda`` to tell links apart.
+- ``remote_bda`` in GAP/GATTS events is the **pseudo address** when this feature is enabled.
+- Call ``esp_ble_gap_get_conn_identity()`` while connected to recover the real peer and local identity.
+- Use ``esp_ble_gap_remove_bond_for_identity()`` to delete one identity's bond without affecting the other.
+- For controller operations (whitelist, directed advertising), use the **real peer** address, never the pseudo.

docs/en/api-guides/ble/index.rst

@@ -15,6 +15,7 @@ Overview
    ble-qualification
    Low Power Mode Introduction <ble-low-power-mode>
    ble-multiconnection-guide
+   :SOC_BLE_50_SUPPORTED: bluedroid-dual-identity-host-dev
 
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