fix: navegación anterior/siguiente compacta en mobile

[mgaitan]

Cierra #129

En mobile, el kicker ("← Anterior" / "Siguiente →") y el título del artículo prev/next se mostraban en dos líneas separadas, quedando visualmente mal.

Cambios

src/styles/site.css

• .article-nav-prev, .article-nav-next: agrega flex items-baseline gap-1 en mobile y sm:block para revertir a layout vertical en desktop.

templates/article.html

• Kicker: agrega shrink-0 para que nunca se comprima.
• Link del título: reemplaza block mt-1 por sm:block sm:mt-1 min-w-0 truncate — inline en mobile (una sola línea), block con margen en desktop; truncación para títulos largos.

Resultado

• Mobile: kicker + título en una sola línea compacta.
• Desktop (≥640px): dos columnas, kicker arriba y título abajo, Siguiente → alineado a la derecha. Sin cambios de diseño.

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Limit truncation to mobile navigation only

When the previous/next title is longer than the nav column, this unconditional truncate also applies at sm and wider breakpoints, so desktop article navigation now hides most of the title with an ellipsis instead of wrapping as it did before. Since the change is for compact mobile navigation and the parent switches back to sm:block, make the truncation mobile-only or undo it at the sm breakpoint so full titles remain visible on desktop.

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