Stellium v0.18.2

A small release with one correctness fix that matters a lot if you use progressions, a community-contributed localization, and a couple of user-requested additions.

Behavior Change: Progression Angle Method Default

If you use progressions, read this.

The default angle_method for progression() has changed from quotidian to solar_arc.

The previous default was producing incorrect progressed angles. Quotidian angles move ~1° per day of offset from the native's birthday — which means a target date 6 months past the birthday produced ~160° of error on the progressed Ascendant. Solar Arc (natal angles + the Sun's progressed arc) matches the behavior of Solar Fire, Astro.com, and professional astrology software generally, and is the correct default for secondary progressions.

# Now the default, matches professional software
builder.progression(date)
builder.progression(date, angle_method="solar_arc")  # explicit, same thing
 
# Still available for advanced timing work
builder.progression(date, angle_method="quotidian")

Affects ComparisonBuilder.progression(), MultiChartBuilder.progression(), and MultiChartBuilder.add_progression(). (Fixes #35, reported by @yykeys)

If you have stored progression results, recalculate becuase the angles will be different (and correct).

New Features

Simplified Chinese Localization (zh_CN) Draft

Frontend UI strings, report section strings, astrology terminology, and PDF report terminology are now available in Simplified Chinese. Contributed by Zhanran Astrology / 湛然星座 (@zx8956-sketch). (#37)

Thanks Zhanran Astrology! This is Stellium's first community-contributed localization and it's a meaningful one.

Sun-Moon Ecliptic Separation in Moon Phase Report

The Moon Phase section now shows the Sun-Moon ecliptic longitude separation (0–360°) alongside the phase name, both inline and as a separate field:

Phase Name:    Waning Gibbous (234°)
Sun-Moon Sep:  234.3°

Useful for verifying phase boundaries against your own classification system. (Closes #31, requested by @daiwei9767)

Infrastructure

pytest capped to <9.0.0: pytest-codeblocks 0.17.0 uses a deprecated API removed in pytest 9.x, causing CI failures. Capped until the plugin releases a compatible version.

Upgrade Notes

pip install --upgrade stellium

The progression default change is the only thing requiring attention. If you were using angle_method="solar_arc" explicitly already, nothing changes. If you were using the default or angle_method="quotidian" without meaning to, your progressed angles will now be correct.