Reads attr(peers, 'cohort_year') when the caller passed a cog_find_peers()
tibble; NA when the caller passed a bare character vector. Stamped as a
constant column on the result and recorded in provenance alongside the
cohort govids.
Adds optional 'year' argument (defaults to most recent observed year for
the target). Filters and ranks candidates by gov_population_yearly.population
at that year. Returned column renamed population_acs -> population.
Cohort year attached as attr(x, 'cohort_year').
Adds .resolve_cohort_year() helper. Updates test assertions to use
'population' column name. Regenerates man/cog_find_peers.Rd.
cog_find_peers selects peers from canonical_fips_xwalk by same-type,
same-state, and population-range (ratio or absolute) criteria,
ordered by |log(pop_ratio)| ascending.
cog_peer_compare accepts the find_peers result (or a plain character
vector of govids), pulls spending for target + peers via cog_spending,
and appends summary rows (summary_p25/p50/p75) so the whole result
can be faceted by `role` in a single ggplot call. Summary rows honor
per_capita + adjust_to_year by picking the right value column.
target_rank reports the target's rank among target+peers at max(years).
Provenance is rewritten with verb = cog_peer_compare and peer_count.
Also: globalVariables('.data') in zzz.R to silence R CMD check on
tidy-eval pronouns.
Tests: 21 new / 120 total pass. devtools::check() 0E/0W/2N.
jared