worldbank 0.8.0

• wb_data() gains mrv and gapfill parameters to query the most recent values and forward-fill missing data.
• wb_project() queries World Bank project data with support for filtering by country, status, region, date range, and free-text search.
• pip_cp() returns country profile data from the PIP API.
• pip_data() gains a nowcast parameter to include nowcast estimates.
• wb_cache_clear() replaces wb_cache_delete(), which is now deprecated.