[PowerDisplay] Confirm before enabling module; log EdidId in Phase 0 (#48111)

## Summary of the Pull Request

Two crash-correlation aids for the kernel-side DDC/CI BSOD mitigated by
#47734:

1. Log EDID hardware ID (manufacturer + product code, e.g. `DELD1A8`)
during Phase 0 monitor classification, before any DDC/CI capability
fetch enters the BSOD risk window.
2. Show a confirmation dialog before turning the Power Display module on
from the Settings page, so the user understands the BSOD risk before the
first capability fetch runs.

## PR Checklist

- [ ] Closes: #xxx
- [x] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [x] **Tests:** Added/updated and all pass
- [x] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

## Detailed Description of the Pull Request / Additional comments

### 1. Phase 0 EdidId logging

`MonitorIdentity.EdidIdFromDevicePath` parses the EDID hardware ID
segment from a DevicePath of the form
``\?\DISPLAY#DELD1A8#5&abc&0&UID12345#{guid}`` and returns ``DELD1A8``.
The 3-letter PNP manufacturer code + 4-hex product code is identical for
every physical unit of the same model, so it identifies the *model*
without leaking per-unit identifiers.

`MonitorManager` logs the EdidId on the existing Phase 0 classification
line. Phase 0 uses `QueryDisplayConfig`, which reads OS-cached EDID and
cannot BSOD, so this line is guaranteed on disk before the crash-prone
Phase 2 capability fetch starts. If a machine crashes during
enumeration, the recovered log identifies every attached model
(including same-model duplicates), which makes it possible to correlate
crash reports to specific monitor models even when the user can't tell
us which monitor caused the crash.

### 2. Enable-module confirmation dialog

`PowerDisplayViewModel.IsEnabled` setter is refactored to follow the
same two-phase pattern already used by `MaxCompatibilityMode`:

- `false → true` does not commit immediately; it kicks off
`ConfirmAndEnableModuleAsync`, which awaits the existing
`DangerousFeatureWarningDialog` (resource prefix
`PowerDisplay_EnableModule`) and either commits or reverts the
ToggleSwitch via `OnPropertyChanged`.
- `true → false` commits unconditionally — we never block a user who
wants to turn the module off.
- App-startup loads via `InitializeEnabledValue()` /
`RefreshEnabledState()` assign the `_isEnabled` field directly,
bypassing the setter, so the dialog never fires on settings restore or
GPO refresh.
- GPO-configured state still short-circuits before any dialog logic.

The dialog reuses the existing `DangerousFeatureWarningDialog` injected
by `PowerDisplayPage.xaml.cs`. The 5 new `PowerDisplay_EnableModule_*`
strings explain that the BSOD is in Windows (not Power Display), that
Power Display will auto-disable itself after a detected crash, and that
the user has to re-enable + dismiss the warning each time.

## Validation Steps Performed

- Built `src/settings-ui` and `src/modules/powerdisplay` locally.
- Unit tests: added `EdidIdFromDevicePath_*` cases to
`MonitorIdentityTests`, all green.
- Settings UI manual: toggling Power Display ON now shows the warning
dialog. Pressing Cancel reverts the ToggleSwitch visually; pressing
Enable commits and the module starts. Toggling OFF does not prompt.
Restarting Settings UI with PowerDisplay enabled does not prompt.
GPO-disabled state still locks the toggle.
- Log inspection: `MonitorManager` Phase 0 log now shows `EdidId=...`
for each path before any capability fetch.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Yu Leng (from Dev Box) <yuleng@microsoft.com>
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: 3 people