feat: three-concept expenditure model classified by crosswalk membership (#11)

Rewrites expenditure/revenue classification off item-code first-letter
prefixes and onto summary_categories membership (F-018: prefix Y spans
revenue, expenditure, and balance codes), and exposes
expenditure_concept = c("primary", "direct", "total") with primary as
the new default:

  primary = operations + capital + assistance
  direct  = primary + interest + insurance_benefits   (Census Direct)
  total   = direct + intergovernmental                (M/L/Q via ig views)

- inst/sql: flow views (20-25) select by crosswalk membership;
  summary_categories moves to 11- so it registers before them (DuckDB
  binds view sources eagerly). The IG leg gains Q11/Q12/Q18 state
  school-system payments (F-017).
- R: one subtype scope per verb call drives the verb SQL, the
  harmonization exclusion count, and the complete = TRUE grid;
  flow_prefixes survives only to scope recipe suggestions.
  cog_geographic_rollup/cog_peer_compare accept primary|direct, still
  refuse total, and now actually pass the concept through.
- Balance codes can never reach a spending or revenue result
  (uscogdata#25), asserted at both view and verb level.
- Deletes the #11 skip; per the 2026-07-30 owner ruling the F-018 Y01
  proof is asserted against the crosswalk, not the default
  cog_revenue() call (which stays General Revenue pending #12).

Suite: 696 pass / 0 fail / 1 skip (#12, expected).

Closes #11

tests/testthat/test-expenditure-concepts.R

@@ -19,8 +19,6 @@
 # also check the FY2022 numbers above.
 
 test_that("expenditure concepts classify on spend_type, not item-code prefix", {
-  testthat::skip("Blocked on uscogdata#11 (findings F-012, F-017, F-018)")
-
   mad      <- "552025209777"   # MADISON CITY, WI
   wi_state <- "550000227544"   # WISCONSIN (state government)
 
@@ -61,15 +59,54 @@ test_that("expenditure concepts classify on spend_type, not item-code prefix", {
 
   # -- F-018: prefix Y splits revenue from expenditure, by spend_type ---------
   # Y01/Y02 are Insurance Trust revenue; Y05/Y06 are Insurance Trust benefit
-  # payments. All four share the first letter `Y` and the spend_type
-  # "Insurance Trust", so this pair of assertions is the concrete proof that
-  # classification is no longer keyed on the first letter.
+  # payments. All four share the first letter `Y`, so no first-letter allowlist
+  # can route them. The proof that classification is crosswalk-keyed:
+  # Y05 lands in `total` spending (insurance_benefits is inside `direct`),
+  # while Y01 -- same prefix -- is classified `revenue` by the crosswalk and
+  # therefore can never appear in a spending result.
+  #
+  # Per the owner's 2026-07-30 ruling (#11 DoD item 4 vs #12), cog_revenue()'s
+  # DEFAULT stays Census General Revenue and so excludes insurance-trust
+  # revenue; Y01's revenue-side classification is asserted against the
+  # crosswalk itself, not the default call. Surfacing Y01 through an explicit
+  # revenue concept argument is uscogdata#12.
   wi_revenue <- cog_revenue(govid = wi_state, years = 2019L)
   spend_codes <- wt_codes_included(wi_total)
   rev_codes   <- wt_codes_included(wi_revenue)
 
   expect_true("Y05" %in% spend_codes)
   expect_false("Y05" %in% rev_codes)
-  expect_true("Y01" %in% rev_codes)
   expect_false("Y01" %in% spend_codes)
+  expect_false("Y01" %in% rev_codes)   # default = general revenue (#12 ruling)
+
+  con <- uscogdata:::.ensure_session()
+  y_class <- DBI::dbGetQuery(con,
+    "SELECT item_code, category_type, spend_subtype, revenue_subtype
+     FROM summary_categories WHERE item_code IN ('Y01', 'Y05')")
+  expect_equal(y_class$category_type[y_class$item_code == "Y01"], "revenue")
+  expect_equal(y_class$revenue_subtype[y_class$item_code == "Y01"], "insurance_trust")
+  expect_equal(y_class$category_type[y_class$item_code == "Y05"], "expenditure")
+  expect_equal(y_class$spend_subtype[y_class$item_code == "Y05"], "insurance_benefits")
+})
+
+test_that("no balance code or category ever reaches a spending or revenue result (uscogdata#25)", {
+  # Stocks are not flows. The crosswalk's balance codes (W/X/Y/Z fund
+  # balances) share first letters with flow codes, so this could never be
+  # guaranteed under prefix classification; under crosswalk membership it
+  # falls out structurally -- asserted here at the verb level, on a
+  # government-year the fixture gives real balance rows (Wisconsin carries
+  # Y07/Y08/Y21/Y61-type balances in FY2019).
+  wi_state <- "550000227544"
+  con <- uscogdata:::.ensure_session()
+  balance <- DBI::dbGetQuery(con,
+    "SELECT item_code, category FROM summary_categories WHERE category_type = 'balance'")
+  expect_gt(nrow(balance), 0L)
+
+  spend <- cog_spending(wi_state, 2019L, expenditure_concept = "total")
+  rev   <- cog_revenue(wi_state, 2019L)
+
+  expect_false(any(spend$category %in% balance$category))
+  expect_false(any(rev$category %in% balance$category))
+  expect_length(intersect(wt_codes_included(spend), balance$item_code), 0L)
+  expect_length(intersect(wt_codes_included(rev), balance$item_code), 0L)
 })