feat(scale): add manual USB-powered override for Skale - #745

Centralize USB-power setting application and remove duplicate state, resets, and test-only interface surface identified during the ponytail review. Discovered devices still receive the setting before connection without publishing inactive metadata.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

The top-right Settings page did not link to the existing Devices page, leaving firmware and scale controls hidden behind the launcher navigation. Add a direct Devices row so connected-device metadata and settings are reachable from the expected entry point.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

The manual USB-power override was rendered as a global switch at the bottom of the Devices page, leaving it effectively hidden and detached from the Skale it configures. Move the control behind a settings button on USB-configurable scale rows without changing its persisted global Skale semantics or battery-refresh behavior. Update the widget coverage and device-management documentation to reflect the discoverable Settings > Devices path.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Device Management is now reachable from the regular Settings page as well as the dashboard. Record both entry points so the user-facing navigation documentation matches the new discoverable route.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

The USB override only produces usb with manualOverride, while the device-information enums and API schemas advertised three unused sources and an unused provenance. Keep the contract honest to implemented behavior, remove serializer-only coverage already exercised through the Devices API, and detect configurable scale rows directly instead of passing a one-use callback through the section builder.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

All three USB propagation tests repeated the same discovery, settings, and controller initialization. Extract that fixture construction into one helper so each test shows only the behavior it varies while retaining explicit cleanup and disposal coverage.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

The USB-power override was global, which made one Skale setting overwrite the power-source behavior of every configurable scale.
Persist enabled device IDs, expose the per-device map through settings export and REST, and apply each value only to its matching device. Disabled entries are removed so the stored contract remains compact and defaults safely to battery reporting.
The native device dialog and tests now verify independent settings for two Skales and same-ID replacement devices.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Expose generic connected-scale metadata through /api/v1/scale/info while keeping device inventory limited to discovery and connection state. Keep metadata refreshes out of the inventory WebSocket and align the API contract.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Use the router's parameterized GET form so the connected-scale metadata endpoint is reachable, and align inventory tests with the boundary.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Keep scale metadata on the connected-scale endpoint and update affected implementations and tests.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Keep inventory payloads metadata-free and cover connected scale info responses.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>