tidyBdE 0.7.0

• Internal code was refactored with AI assistance to reduce duplication in
  indicator wrappers and ggplot2 scale helpers.
• Messages and package errors now use cli, with AI-assisted wording updates
  and without the former tidyBdE> prefix.
• roxygen2 documentation was reviewed with AI assistance and tag order was
  made consistent across source files.
• Tests were refactored and expanded with local fixtures, mocks and snapshot
  updates, reaching 100% line coverage in devtools::test_coverage().
• New vignette vignette("csv_manual", package = "tidyBdE") explaining the
  structure of Banco de España bulk CSV files, catalog metadata and series
  identifiers (#64).
• New Statistics web service (API) functions added (#65):
  • bde_series_api_latest() added to query the Latest Data request of the
    Banco de España Statistics web service
    (API).
  • bde_series_api_load() added to query the Series List request of the Banco
    de España Statistics web service (API), with support for wide and long
    output, metadata extraction and time range validation.
• ?bde_ind_db has been updated, including the field Nombre_de_la_serie (API
  series code); see ?bde_series_api.