Change filter width column to `effective_width_angstroms`

In the PhotometryFilters table, we ingest the filter width provided by the SVO service. SVO provides both the FWHM and the effective width. Does anyone have strong or informed opinions about which ones of these we should use for "width"?

Inspect the PhotometryFilters table and the SVO ingestion path to locate how the current filter width is stored. Compare the SVO FWHM and effective-width values, resolve which meaning the width column should represent, and confirm the schema and data update requirements before implementation.

Written by the indexing model from the issue text.