fix(reports): count reversed originals in the KPI monthly breakdown (#2201) (#2243)

The year total (tb / tb_ex_year_end) aggregates posted AND reversed
entries, so a same-year storno nets to 0. The monthly section, both the
get_kpi_report_aggregates RPC and the dimension-filtered JS fallback in
lib/reports/monthly-breakdown.ts, was posted-only: it dropped the reversed
original but kept the storno (itself posted). 10 000 kr on 3041 in March,
reversed in April, gave March 0 kr, April -10 000 kr, year 0 kr, and PR
#2198 made the per-month figures visible enough to add up.

Migration 20260903160000 replaces the RPC with the monthly join on
tb_ex_year_end's entry set verbatim (no extra status predicate); the JS
fallback filters status in ('posted','reversed') the same way. The pg-real
pin ("in tb, not in monthly") is flipped and a storno case asserts
sum(months) = net result. Everything else in the function is byte-identical
to 20260730090000.

Verified: pg-real suite against a rebuilt local supabase/postgres with every
migration applied (9 tests), unit suite, lint.

Closes #2201


Claude-Session: https://claude.ai/code/session_01VnConrmMCxJRQ5kfiPPWyy

Co-authored-by: Jakob Wennberg <311770904+jakobwennberg-oss@users.noreply.github.com>
Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

DECISIONS.md

@@ -1527,5 +1527,6 @@ One line per decision: `[YYYY-MM-DD] <decision>: <why>`. Appended by agents and
 [2026-09-03] Old-address social identities are unlinked by a BEFORE UPDATE trigger on auth.users (migration 20260903110000), not by the /auth/callback done path: the callback never runs for a completing click from a browser without a session, and admin-side changes bypass it entirely; the trigger covers every path and keeps the email identity, password and BankID intact.
 [2026-09-03] AGI redovisningsperiod = the payout month (agiReportingPeriod on payment_date), not salary_runs.period_*: Skatteverket files per the month the pay went out (kontantprincipen), so lön i efterskott (August work paid 25 September) is declared in September. The in-period payment-date guard (dashboard PATCH, lib/salary/update-run.ts, v1 PATCH, RunHeader min/max) is lifted rather than widened: its only stated reason was that the AGI keyed on period_*, and any residual month window would bite the next efterskott variant. Existing agi_declarations rows keep their stored period (no backfill): a declaration already filed under the earned month is a real-world correction with Skatteverket, not a re-key. New AGI_PERIOD_CONFLICT (409) refuses to overwrite a live run's declaration for the same payout month, since one month's AGI must cover every payment that month and the generator cannot merge runs. Issue #2191.
 [2026-09-03] The cursor:// deeplink is its own allowlist provider (cursor_deeplink) rendered "Din egen dator" and never "Verifierad", after the skeptic, CodeRabbit and Superagent all made the same point: a custom scheme can be claimed by any local app (RFC 8252 section 8.4), so it carries loopback trust, not vendor trust, and the consent page must not say otherwise; https://www.cursor.com/... keeps the verified label. Same pass fixed the consent-page CSP for custom schemes: new URL('cursor://...').origin is the string "null", so form-action became `'self' null` and Chromium would have blocked the post-consent 303 (correctness skeptic refutation); the header now uses the scheme-source (`cursor:`) when the origin is opaque. Not done: rejecting a missing code_challenge at /authorize. A code minted without one is unexchangeable (verifyPkce against an empty challenge is always false, now pinned by a test), so it is fail-closed; making it fail earlier is a separate change touching every client.
+[2026-09-03] KPI monthly breakdown counts reversed originals (#2201): the monthly section of get_kpi_report_aggregates (new migration 20260903160000) and lib/reports/monthly-breakdown.ts now use tb_ex_year_end's entry set verbatim (posted + reversed, minus the undone year-end chain) instead of posted-only. A same-year storno then cancels inside the months as it does in the year total, so sum(months) = Nettoresultat; the reversal shows as negative revenue in its own month, which is the honest month view. The pg-real pin "in tb, not in monthly" was flipped, not worked around. Unblocks the per-month sum on Nyckeltal (#2196).
 [2026-09-03] customers.country and suppliers.country are ISO 3166-1 alpha-2 at every writer (form select, internal + v1 REST, MCP, imports, provider migration), normalised through one helper (lib/vat/country-codes.ts) that also accepts the Swedish/English names the form used to write; unknown text is a 400 on write and left as-is by the backfill (migration 20260903170000 keeps the original in country_raw for a one-UPDATE rollback, and derives the country from the VAT prefix for eu_business rows whose country was null or only the old writer default SE: on prod that is one validated row plus sixteen without a country, and without it they would flip from reverse charge to 25% on their next invoice). No CHECK constraint on the column: unmapped legacy rows would violate it, and the periodisk report already warns on those. The country-vs-type rule (swedish_business = SE, eu_business = not SE and either in the EU VAT area with a matching prefix or holding an EU-trade VAT registration such as a Swiss company with a DE number or Northern Ireland XI, non_eu_business = outside the EU) is enforced on customers only, and on update only when type, country or VAT number is part of the change so a contradictory legacy row can still change its email; individuals are free (a foreign private person is still a Swedish-VAT customer) and suppliers get normalisation without the rule, since #2025/#2028 are about sales VAT. An omitted country on create is SE for Swedish types, derived from the VAT prefix for eu_business, and a 400 for non_eu_business: guessing a non-EU country is not possible, and Sweden-by-default was the bug. vat-rules.ts takes the country as a third optional argument and refuses reverse charge only for SE (a VIES-validated number outweighs a non-EU address), and not for an unknown/unmapped country: charging Swedish VAT to a genuine German customer whose row says Deutschland (Bayern) would be the worse error.
 [2026-09-03] AGI kvittens cron: dropped the apigw_config bucket (#963) and its warn-once suppression for ACCESS_DENIED (#2226). The bucket existed because the APIGW client was known to lack the AGI hantera subscription in Utvecklarportalen; with that subscription expected in place, a gateway refusal is a regression and belongs in the ordinary error path (error level, generic 'error' status) rather than a status that hides it as a known gap. Same pass: the connector-mode gateway-refusal message names the connector operator by host instead of "kontakta supporten", because hosted is itself a Connect installation for the canary companies and "support" no longer says whose. Merging before the portal subscription is active means the 15-minute cron logs at error level per pending declaration until it is.