Release Hass-Cleaner 1.0.0

[dkwolf1]

Summary

• marks Hass-Cleaner 1.0.0 as the first stable release
• relies on Home Assistant's default stable stage by omitting the redundant stage field
• adds a prominent Dutch/English early-tester warning
• updates the README, changelog, and roadmap for the V1 release
• adds a regression test that prevents the default stage field from being reintroduced

Why

The functional V1 scope is complete and the repository is protected. This pull request publishes the release status and documentation without adding new cleanup functionality.

The initial lint run failed because Home Assistant requires the redundant stage: stable setting to be omitted. The manifest now follows that requirement.

User impact

Users see version 1.0.0 as a stable app, with an explicit warning to review every selection, create a full Home Assistant backup first, and preferably begin on a non-critical installation.

Validation

• 68 Python tests passed
• 1 Windows symlink test skipped because it requires additional privileges
• JavaScript syntax checks passed
• Python compileall passed
• git diff --check passed