#705 - add LV Battery voltage tile to eFuses page

[bracyw]

Changes

Redesigns the LV Battery presentation on the eFuses page as a reusable, read-only "Quick view" status bar pinned to the top-right of the page, out of the eFuse command zones. It is a right-edge sidebar pop-out that auto-opens, collapses to a small edge handle, and stays available (sticky) while the eFuse cards scroll beneath it.

On the bar sits an LV Battery chip: live voltage from VCU/LV/voltage with a status dot that turns red on the LV low-voltage fault (VCU/Faults/Non-Critical/LV_LOW_VOLTAGE_FAULT) and stays green otherwise. The warning is driven purely by the firmware fault flag, never a hardcoded voltage cutoff. This represents the physical low-voltage battery, distinct from the LV eFuse card (VCU/eFuses/LV/Voltage).

This is the foundation for #709 (customizable status bar for user-pinned topics): the bar projects chips and is built to hold more later.

Frontend-only: telemetry ingest is schemaless (Topic = DataType), so there is no scylla-server, Charybdis, or Siren change.

Notes

The status bar is a reusable component at src/components/status-bar (projects chips via ng-content), with the LV Battery chip at efuses-page/components/lv-battery-chip. Telemetry is read as signals through the existing storage seam under zoneless change detection, with no new services or backend contracts. The page host is set to display block so the sticky bar's containing block spans the full page.

Accessibility and theming: the fault is announced by an aria-label on the status dot rather than color alone, the collapse and re-open controls carry visible focus rings, focus moves to the successor control on toggle so keyboard users are not dropped to the page body, the slide-in animation respects prefers-reduced-motion, and all colors use the shared theme tokens. Both new components ship with co-located unit specs.

Test Cases

• Open (default): the bar auto-opens top-right with the "Quick view" header; the LV chip shows live voltage with a green dot (nominal).
• Scroll: the bar pins to the top-right corner while the eFuse cards scroll beneath it.
• Collapse / re-open: the chevron retracts the bar to a small edge handle, which re-opens it on click; focus moves to whichever control is now shown, with a visible focus ring.
• Fault raised: the status dot turns red and its accessible label switches to a fault message, driven by the firmware fault flag independent of the voltage reading.
• Unit specs: chip voltage formatting and placeholder, the fault label, and status-bar toggle, projection, and focus — all green.
• build / lint / prettier / ng test: green.

Screenshots

Quick View Tab (not popped out)

Quick View Popped out

Quick View Popped Out during scroll

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Closes #705.