Add SI units for additional quantities and common non-trivial units

[gdtroszak]

Track SI unit additions in two categories:

1. New unit modules for quantities added in Add additional ISQ derived quantities #10 — each needs at least the base SI unit
2. Additional non-trivially-scaled units for new and existing modules — units whose scaling factors are not simple SI prefixes (e.g., kilometerPerHour, revolutionPerMinute, gramPerLiter)

Prefixed variants (e.g., kilonewtonMeter, millinewtonMeter) are easy to compose with unit.scaled(KILO) and do not need pre-defined exports.

Each item follows the adding a new SI unit checklist. New modules are blocked on the corresponding quantity existing in dim-isq (#10).

New unit modules (blocked on #10)

Each checkbox represents a new module with its base SI unit. Non-trivial additional units are listed inline.

• density — kilogramPerCubicMeter; also gramPerLiter, gramPerCubicCentimeter
• specificVolume — cubicMeterPerKilogram
• momentum — newtonSecond
• angularVelocity — radianPerSecond; also revolutionPerMinute
• angularAcceleration — radianPerSecondSquared
• torque — newtonMeter
• dynamicViscosity — pascalSecond
• kinematicViscosity — squareMeterPerSecond
• surfaceTension — newtonPerMeter
• heatCapacity — joulePerKelvin
• specificHeatCapacity — joulePerKilogramKelvin
• specificEnergy — joulePerKilogram
• thermalConductivity — wattPerMeterKelvin
• electricFieldStrength — voltPerMeter
• permittivity — faradPerMeter
• permeability — henryPerMeter
• currentDensity — amperePerSquareMeter
• volumetricFlowRate — cubicMeterPerSecond; also literPerSecond, literPerMinute
• massFlowRate — kilogramPerSecond
• concentration — molePerCubicMeter; also molePerLiter
• molarMass — kilogramPerMole; also gramPerMole
• wavenumber — reciprocalMeter

Additional units for existing modules

Non-trivially-scaled units for modules that already exist.

• velocity — kilometerPerHour
• charge — ampereHour, milliampereHour
• pressure — atmosphere
• area — squareKilometer, squareCentimeter