Add host temperature metrics card

[ZacharyZcR]

Summary

• collect host temperature sensors from Linux thermal sysfs with an lm-sensors fallback
• add a Host Metrics temperature card showing the highest reading and sensor list
• include temperature in default metric widgets and translated locale keys

Notes

• This displays hardware thermal sensors exposed by the host OS. It does not attempt GPU-specific tools or metrics history storage in this PR.

Verification

• npx vitest run src/backend/ssh/widgets/temperature-collector.test.ts
• npx prettier --check .
• npx tsc --noEmit
• npm run lint
• npm run build

Fixes Termix-SSH/Support#890