Calibration 2/5 stays on AC power at 100% on macOS 27 with AlDente 1.39 (M5)

**MacBook (please complete the following information):**
- MacBook Model: MacBook Pro, Mac17,2, Apple M5
- macOS Version: macOS 27.0 (26A5425a)
- Charger Model: 90 W power adapter
- Charging Cable: Unknown
- AlDente Pro or AlDente Free: AlDente Pro
- AlDente Version: 1.39 (Build 107)
- Relevant settings: Calibration Mode active; Automatic Discharge enabled; Sailing Mode enabled with 5% range; Heat Protection disabled; Hardware Battery Percentage disabled; native macOS charge-limit integration enabled
- Debug file: Not attached yet
- External Monitor connected: Yes
- MacBook used in Clamshell Mode: Yes

**Describe the bug**
Calibration Mode advances to step 2/5, “Discharge to 10%”, after reaching 100%, but the MacBook continues to run from AC power and the battery does not discharge. AlDente shows adapter power around 27.8 W, MacBook consumption around 28.7 W, and battery power 0.0 W. macOS reports that the battery is not charging, but it is also not supplying power.

This appears related to #1784, but that report stalls at 11%. This reproduction stalls immediately at 100% on an M5 MacBook.

**To Reproduce**
1. Connect the 90 W adapter and use the MacBook in clamshell mode with an external monitor.
2. Start Calibration Mode.
3. Allow step 1/5 to charge the battery to 100%.
4. Wait for Calibration Mode to advance to step 2/5, “Discharge to 10%”.
5. Observe that the system remains on AC power and the battery remains at 100%.

**Expected Behavior**
During step 2/5, AlDente should internally disconnect the adapter as a power source and run the MacBook from the battery until it reaches 10%.

**Actual Behavior / Diagnostics**
- `pmset -g batt`: `Now drawing from AC Power`; battery `100%; charged`
- `system_profiler SPPowerDataType`: adapter connected, `Charging: No`
- AppleSmartBattery: `IsCharging = No`, `InstantAmperage = 0`, `BatteryPower = 0`
- Five samples over 15 seconds all remained at 100% and 0 A
- Both AlDente and its privileged helper were running

No settings were changed while collecting these diagnostics.

Start by reproducing Calibration Mode's transition from step 1/5 to step 2/5 on the stated M5 macOS setup, using the 90 W adapter, external monitor, and clamshell mode. Read the power-state diagnostics from pmset -g batt and system_profiler SPPowerDataType alongside the AppleSmartBattery values. Done means step 2/5 runs from battery rather than AC and discharges toward 10%.

由索引模型根据 Issue 内容生成。