Fix choropleth horizontal line artifacts on projected maps (#668)

* Fix choropleth horizontal line artifacts on projected maps

Use Cartopy's project_geometry() instead of transform_points() for
choropleth polygon projection. transform_points() projects vertices
independently without geometric awareness, so polygons crossing the
antimeridian (e.g. Russia) produce path segments that jump across the
entire map, rendering as visible horizontal lines.

project_geometry() properly splits and clips polygons at projection
boundaries before converting to matplotlib paths, eliminating the
artifacts on all projections (Robinson, Mercator, Mollweide, etc.).

* Black

Release v2.1.3

Fix contour level color mapping with explicit limits (#599)

* Fix contour level color mapping with explicit limits

* Update ultraplot/axes/plot.py

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* Fix `_parse_level_norm` docstring to reflect conditional return type (#600)

* Initial plan

* Update _parse_level_norm docstring Returns section to reflect possible return types

Co-authored-by: cvanelteren <19485143+cvanelteren@users.noreply.github.com>

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Casper van Elteren <caspervanelteren@gmail.com>
Co-authored-by: cvanelteren <19485143+cvanelteren@users.noreply.github.com>

* Scope explicit contour limits to line contours

* Pass vmin/vmax through automatic level generation

* Restore default tricontour discrete mapping

* Format contour norm routing changes

* Clarify contour norm routing docs

* Refactor contour norm routing flow

* Refactor contour norm routing flags

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Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <198982749+Copilot@users.noreply.github.com>
Co-authored-by: cvanelteren <19485143+cvanelteren@users.noreply.github.com>

Fix cartopy tri default transform for Triangulation inputs (#595)

Make docs theme dependency RTD-only and PyPI-safe

Updated docs theme (#585)

* Docs theme-v2: refine nav/TOC styling and add code visibility controls

* Docs theme-v2: apply dark code-surface backgrounds consistently

* Docs theme-v2: hide right TOC on gallery listing pages

* update theme and makefile

* Docs: wire optional UltraTheme assets and refresh homepage visual system

* Docs TOC UX: hide collapse controls when unused and move Hide action to title row

* Numerous fixes across different docs and part of the api

* Make plots blend with background

* Docs: full-width notebook outputs and add missing font_table anchor

* Docs: style header brand text with multi-shade green gradient

Merge remote-tracking branch 'origin/main' into release/v1.72.0

Ignore ipynb for based pyright

added inference of labels for spanning legends (#447)

Add external context mode for axes (#406)

* add seaborn context processing

* rm debug

* add unittest

* resolve iterable

* relax legend filter

* add seaborn import

* add more unittests

* add ctx texts

* implement mark external and context managing

* fix test

* refactor classes for clarity

* update tests

* more fixes

* more tests

* minor fix

* minor fix

* fix for mpl 3.9

* remove stack frame

* adjust and remove unecessary tests

* more fixes

* add external to pass test

* restore test

* rm dup

* finalize docstring

* remove fallback

* Apply suggestion from @beckermr

* Apply suggestion from @beckermr

* fix bar and test

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Co-authored-by: Matthew R. Becker <beckermr@users.noreply.github.com>