Score all gallery templates and recommend the best fit.
Call this AFTER profiling the data source and deciding on chart
types, but BEFORE creating the dashboard layout. The decider
evaluates every template in the gallery against the data profile
and chart mix, returning a ranked list with reasoning.
Args:
chart_types: Comma-separated list of chart mark_types being built.
Example: "Bar,Line,Text,Text,Map"
If omitted, uses only the data profile signals.
kpi_count: Override KPI count (else derived from chart_types).
Returns:
Ranked template recommendations with scores and reasoning.
Connector