Feature Request: Expose mowing schedule as a Calendar entity (read-only)

[thphilipp]

Problem

Mowing schedules configured in the Mammotion app are not visible anywhere in Home Assistant. To check when the mower will run next, users have to switch back to the app. For users who build comprehensive dashboards around the mower (live status, telemetry, diagnostics, lifetime statistics, etc.) this is the missing piece — there's no way to see what is planned alongside what is happening now.

This is the read-only counterpart of #555 (which focuses on modifying the schedule from HA). Read access alone would already cover most dashboard and automation use cases, and could be a useful first step before tackling the write side.

Proposed solution

Expose the mower's schedule as a native Home Assistant Calendar entity (e.g. calendar.<mower_name>).

Why a Calendar entity (vs. a sensor with JSON attributes):

• Renders directly in HA's built-in type: calendar Lovelace card (week / month / list views) — no custom templating required.
• Standard interface: state = next event, attributes = upcoming events.
• Drives automations via the calendar trigger (e.g. "notify 15 min before the next mow", "auto-skip if rain forecast", "pause household audio during mowing").
• Composable with family calendars and household routines — users can see their week including planned mows in one place.

Each scheduled mow would become a calendar event with:

• summary: zone or task name
• start / end: scheduled time / expected duration
• description (optional): cutting parameters (speed, blade height, mowing laps, etc.)

Why this should be feasible

Per #555, the schedule data is already retrieved by the integration — it appears in debug logs and device attributes (work.non_work_periods, quiet_hours, schedule entries, etc.) but is never surfaced to HA in any entity. The data pipeline exists; only the CalendarEntity mapping (async_get_events) is missing.

Alternatives considered

• Sensor with JSON attribute list: works but requires custom Jinja templating and markdown cards on the user side — far less clean than a native Calendar entity.
• External input_datetime helpers driven by user-written scripts (e.g. Peter Blandford's setup): a parallel system that does not reflect what is actually programmed on the mower — only what the user re-implements in HA.

Neither alternative reflects the actual schedule on the device.

Setup

• Model: Luba VAE3FTSE
• Connection: WiFi
• Integration version:

Thanks for the excellent work on this integration!