Add ppm to NITROGEN_DIOXIDE units

[lboue]

Proposed change

Added support for ppm to NITROGEN_DIOXIDE units

Type of change

• Document existing features within Home Assistant
• Document new or changing features for which there is an existing pull request elsewhere
• Spelling or grammatical corrections, or rewording for improved clarity
• Changes to the backend of this documentation
• Remove stale or deprecated documentation

Checklist

• I have read and followed the documentation guidelines.
• I have verified that my changes render correctly in the documentation.

Additional information

• This PR fixes or closes issue: Entity sensor.air_quality_sensor_nitrogen_dioxide (<class 'custom_components.matter.sensor.MatterSensor'>) is using native unit of measurement 'ppm' which is not a valid unit for the device class core#150763
• Link to relevant existing code or pull request: Add ppm to NITROGEN_DIOXIDE units core#162983

Summary by CodeRabbit

Documentation

• Added ppm as a supported measurement unit for nitrogen dioxide, alongside ppb and μg/m³, in the air quality docs and number device-class guidance.
• Expanded sensor device class documentation to list 30+ additional available classes (e.g., pH, PM1/PM2.5/PM10, power, pressure, temperature, voltage, wind speed, VOCs, precipitation, signal strength, and more).

[coderabbitai]

📝 Walkthrough

Walkthrough

Documentation updates adding ppm as a supported unit for nitrogen dioxide and expanding the sensor device classes table with many additional entries.

Changes

Cohort / File(s)

Summary

Device class / sensor docs docs/core/entity/air-quality.md, docs/core/entity/number.md, docs/core/entity/sensor.md

Added ppm to the supported units for nitrogen dioxide. Expanded the sensor device classes table to include new classes such as PH, PM1, PM25, PM4, PM10, POWER, POWER_FACTOR, PRECIPITATION, PRECIPITATION_INTENSITY, PRESSURE, REACTIVE_ENERGY, REACTIVE_POWER, SIGNAL_STRENGTH, SOUND_PRESSURE, SPEED, SULPHUR_DIOXIDE, TEMPERATURE, TEMPERATURE_DELTA, TIMESTAMP, VOLATILE_ORGANIC_COMPOUNDS, VOLATILE_ORGANIC_COMPOUNDS_PARTS, VOLTAGE, VOLUME, VOLUME_FLOW_RATE, VOLUME_STORAGE, WATER, WEIGHT, WIND_DIRECTION, WIND_SPEED, and others.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

🚥 Pre-merge checks | ✅ 3 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Merge Conflict Detection	⚠️ Warning	❌ Merge conflicts detected (25 files): ⚔️ blog/2022-05-12-s6-overlay-base-images.md (content) ⚔️ blog/2023-11-06-public-addon-config.md (content) ⚔️ docs/android/get_started.md (content) ⚔️ docs/api/rest.md (content) ⚔️ docs/api/supervisor/endpoints.md (content) ⚔️ docs/api/supervisor/models.md (content) ⚔️ docs/core/entity/air-quality.md (content) ⚔️ docs/core/entity/number.md (content) ⚔️ docs/core/entity/sensor.md (content) ⚔️ docs/core/entity/update.md (content) ⚔️ docs/core/integration-quality-scale/rules/discovery.md (content) ⚔️ docs/core/integration-quality-scale/rules/docs-examples.md (content) ⚔️ docs/dev_101_services.md (content) ⚔️ docs/development/labs.md (content) ⚔️ docs/development_environment.mdx (content) ⚔️ docs/development_guidelines.md (content) ⚔️ docs/documenting/create-page.md (content) ⚔️ docs/operating-system/debugging.md (content) ⚔️ docs/operating-system/partition.md (content) ⚔️ docs/voice/pipelines/index.md (content) ⚔️ docusaurus.config.js (content) ⚔️ package.json (content) ⚔️ sidebars.js (content) ⚔️ static/_redirects (content) ⚔️ yarn.lock (content) These conflicts must be resolved before merging into master.	Resolve conflicts locally and push changes to this branch.

✅ Passed checks (3 passed)

Check name	Status	Explanation
Description check	✅ Passed	The description follows the template with all required sections completed: proposed change is described, type of change is selected, checklist items are checked, and additional information includes issue and PR references.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Title check	✅ Passed	The title accurately summarizes the main change: adding ppm support to NITROGEN_DIOXIDE units across documentation files.

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✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch nitrogen_dioxide_ppm

⚔️ Resolve merge conflicts (beta)

• Auto-commit resolved conflicts to branch nitrogen_dioxide_ppm
• Create stacked PR with resolved conflicts
• Post resolved changes as copyable diffs in a comment

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[coderabbitai]

Actionable comments posted: 2

🤖 Fix all issues with AI agents

In `@docs/core/entity/air-quality.md`:
- Line 32: The unit string for nitrogen_dioxide in the air-quality entity row
currently uses the Greek mu character "μ" — change it to the micro sign "µ" so
it matches the other sensor/number tables; update the value in the
nitrogen_dioxide row (the cell containing "μg/m³") to "µg/m³" and scan other
entity docs for any remaining "μg/m³" occurrences to standardize them all to
"µg/m³".

In `@docs/core/entity/climate.md`:
- Around line 76-88: Update the preset list in docs/core/entity/climate.md to
only include the actual Home Assistant built-in climate presets: ACTIVITY, AWAY,
BOOST, COMFORT, ECO, HOME, NONE, and SLEEP; remove the unsupported entries
GOING_TO_SLEEP, VACATION, and WAKE (or replace them with the correct equivalents
such as mapping GOING_TO_SLEEP→SLEEP and VACATION→AWAY) and, if desired, add a
short note that any other presets are custom to an integration and must be
explicitly defined there.

[coderabbitai]

Actionable comments posted: 1

🤖 Fix all issues with AI agents

In `@docs/core/entity/sensor.md`:
- Line 62: Revert the documentation change that added "ppm" as a supported unit
for SensorDeviceClass.NITROGEN_DIOXIDE in the sensor.md entry and restore the
previous unit list (ppb, µg/m³) until the core PR `#162983` is merged; ensure the
sensor.md text no longer mentions "ppm" or any other units/features that depend
on the draft core change and leave a brief comment or TODO referencing the core
PR number to re-add the unit once that PR is merged.

[Copilot]

Pull request overview

This PR adds support for the ppm (parts per million) unit to the NITROGEN_DIOXIDE device class, expanding the supported units from ppb, µg/m³ to ppb, ppm, µg/m³. This change aligns with a fix in Home Assistant core (issue #150763 and PR #162983) where the missing ppm unit was causing integration issues.

Changes:

• Added ppm to supported units for SensorDeviceClass.NITROGEN_DIOXIDE in sensor documentation
• Added ppm to supported units for NumberDeviceClass.NITROGEN_DIOXIDE in number documentation
• Added unit documentation to the nitrogen_dioxide property in air quality entity documentation

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
docs/core/entity/sensor.md	Added ppm to the supported units for SensorDeviceClass.NITROGEN_DIOXIDE
docs/core/entity/number.md	Added ppm to the supported units for NumberDeviceClass.NITROGEN_DIOXIDE
docs/core/entity/air-quality.md	Added supported units documentation (ppb, ppm, µg/m³) to the nitrogen_dioxide property description

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[MartinHjelmare]

There are no changes at all now in this PR.