v1.6.0: Cross-entity template references

What's Changed

Added

• Cross-entity references in templates: Templates can now reference any entity's state using
  states('entity_id') syntax, enabling multi-entity cells from a single entity slot
  • Syntax: {{ states('entity_id') }}
  • Supports all existing filters: {{ states('sensor.wind_dir') | round(0) }}
  • Example: text_template: "{{state|round(0)}} mph @ {{states('sensor.wind_dir')|round(0)}}"
  • Card automatically re-renders when any template-referenced entity changes state

Changed

• Updated all dependencies to latest versions (lit 3.3.2, rollup 4.60.1, typescript 6, eslint 9,
  typescript-eslint 8, all @rollup/plugin-* to latest majors, custom-card-helpers 2.0.0)
• Migrated ESLint config to flat config format (eslint.config.js) required by ESLint 9
• Updated TypeScript moduleResolution from deprecated node to bundler
• Updated softprops/action-gh-release GitHub Action to v2

Fixed

• Removed unused IconConfig import in indicator-grid-card.ts