fix: align hue budget with supertensor — per-row instead if figure-wide

Adopt per-row ≤4 active hue families, matching supertensor's documented
behavior. Also changed tests/lint-invalid/hue-budget.tex to use \sfrow
so the per-row rule actually triggers.

tests/lint-invalid/hue-budget.tex

@@ -6,9 +6,11 @@
 \sfsetrole{d}{sfViolet}
 \sfsetrole{e}{sfInk}
 \begin{document}\begin{tikzpicture}
-\sfnode[role=a, at={(0,0)}]{A}{A}{8mm}{8mm}
-\sfnode[role=b, at={(12mm,0)}]{B}{B}{8mm}{8mm}
-\sfnode[role=c, at={(24mm,0)}]{C}{C}{8mm}{8mm}
-\sfnode[role=d, at={(36mm,0)}]{D}{D}{8mm}{8mm}
-\sfnode[role=e, at={(48mm,0)}]{E}{E}{8mm}{8mm}
+\sfrow{R1}{14mm}
+  \sfnode[role=a]{A}{A}{8mm}{8mm}
+  \sfnode[role=b]{B}{B}{8mm}{8mm}
+  \sfnode[role=c]{C}{C}{8mm}{8mm}
+  \sfnode[role=d]{D}{D}{8mm}{8mm}
+  \sfnode[role=e]{E}{E}{8mm}{8mm}
+\sfrowend
 \end{tikzpicture}\end{document}