fix(hid): improve composite keyboard and mouse support on iPadOS

[s-qin]

fix(hid): improve composite keyboard and mouse support on iPadOS

Problem

The BLE advertisement classified the peripheral as a plain HID keyboard (Appearance 0x03C1, HID Keyboard) while the device is actually a keyboard + mouse composite HID peripheral. iPadOS then did not expose its native pointer unless AssistiveTouch was enabled.

Observed behavior (before the fix, real hardware)

• kbd_subscribed=true, mouse_subscribed=true — both HID report subscriptions active
• keyboard reports delivered (typed text worked on iPad)
• mouse report command acknowledged by the daemon
• AssistiveTouch OFF: no iPadOS pointer
• AssistiveTouch ON: pointer appeared immediately

Fix

guest/openspan_ble.py: change the advertisement Appearance from 0x03C1 (HID Keyboard) to 0x03C0 (Generic HID) — the peripheral is a keyboard + mouse composite, so it is advertised as generic human interface. No report-map / HID descriptor / GATT changes: mouse reports already worked; this is a compatibility classification fix made as a single-point minimal change.

Validation

Manually tested on real hardware (fresh BLE re-pair after the change):

• AssistiveTouch OFF
• native iPadOS pointer appears
• movement works
• click works
• scroll wheel works
• keyboard still works
• no dependence on AssistiveTouch

Note: the wording describes observed iPadOS compatibility behavior on real hardware tests, not internal iPadOS behavior claims.

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