feat(battery): add options to toggle percentage and remaining time

[hthienloc]

Description

This PR implements customization options for the battery widget on the Dank Bar:

• Adds two toggle options to the battery widget's 3-dot context menu under Dank Bar settings:
  • Show Percentage: Toggles the display of battery percentage (e.g., 95%) on the bar pill.
    • Only on Battery (Sub-toggle): Only visible and active when "Show Percentage" is enabled. When active, it hides the percentage text when the laptop is plugged in / charging (only displaying it when discharging on battery).
  • Show Remaining Time: Toggles the display of remaining time (e.g., 3h 15m / 45m) on the bar pill.
    • Only on Battery (Sub-toggle): Only visible and active when "Show Remaining Time" is enabled. When active, it hides the remaining time text when the laptop is plugged in / charging (only displaying it when discharging on battery).
  • If both are enabled (and visible), the pill displays them combined as 95% (3h 15m).
• Adjusts the context menu width to 270 to prevent translation cut-offs (such as "Show Percentage" cutting off in narrow configurations).

Type of change

• New feature (non-breaking change that adds functionality)

Related issues

Closes #1853

Screenshots / video

Checklist

• My code follows the conventions in CONTRIBUTING.md
• I have tested my changes locally
• New user-facing strings are wrapped in I18n.tr() with translator context, reusing existing terms where possible
• Go changes: ran make fmt, added/updated tests, make test passes, and go mod tidy is clean
• QML changes: ran make lint-qml with no new warnings

[Purian23]

Thanks for the PR!

1. Add SettingsSpec.js entries The four new globals (showBatteryPercent, showBatteryPercentOnlyOnBattery, showBatteryTime, and showBatteryTimeOnlyOnBattery) aren't in settings spec yet. Let's get those added near the other widget defaults.

2. Vertical bar combined display The horizontalDisplayText combines percent + time, but verticalDisplayText drops the time when percentage is on.

Everything else looks good, appreciate the contribution!

[hthienloc]

@Purian23 I made some changes to the battery widget in the vertical bar to make it look more symmetrical when using the remaining time option.