fix(bookkeeping): reverse-charge VAT in booking templates is 25% of the base, not 20% (#1494)

* fix(bookkeeping): reverse-charge VAT in booking templates is 25% of the base, not 20%

applyTemplate() extracted VAT out of the total (rate/(1+rate)) for every
vat line, including the fiktiv-moms pair of reverse-charge templates.
Under omvand skattskyldighet the supplier charges no VAT, so the total IS
the beskattningsunderlag: on 807.99 kr the seeded EU-purchase template
booked 161.60 kr (20%) on 2614/2645 instead of 202.00 kr (25%),
understating Ruta 30-32 and Ruta 48 on the momsdeklaration.

Fiktiv-moms lines (2614/2624/2634 output, 2615/2625/2635 import,
2645/2647 input) now compute amount x rate on top of the base.
deriveTemplateLinesFromBooking ("Spara som mall") gets the mirror fix:
RC legs no longer inflate the derived total (they net to zero), and RC
rates snap against the base, so a correct RC booking round-trips.

Counterparty/SIE learned patterns already strip RC legs and regenerate
them via generateReverseChargeLines with the gross base; those paths
were correct and are unchanged.

User-reported: "Er automatiska utrakning ar pa 20%, inte 25%".

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* fix(bookkeeping): use roundOre for template VAT rounding (guard ratchet)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* docs(bookkeeping): clarify fiktiv-moms comment: total is the base, booked amount is the VAT

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

DECISIONS.md

@@ -850,4 +850,5 @@ One line per decision: `[YYYY-MM-DD] <decision>: <why>`. Appended by agents and
 [2026-08-10] Transactions inbox fetches ALL pending rows merged into the single transactions state array (tracked window boundary via pagedCountRef/pagedThroughDate) instead of a parallel pendingTransactions state: ~20 setTransactions mutation call sites (book/ignore/edit/delete) would each need dual updates and would drift; the merged array keeps mutations one code path, at the cost of a date-boundary filter for the history view.
 [2026-08-09] /migrate streaming is opt-in via Accept: application/x-ndjson instead of replacing the JSON contract: the wizard is the only caller today but a hard cutover would break open pre-deploy tabs and the route's locked error-status tests; mid-stream failures re-send the structured envelope as a terminal error event because the 200 is already committed once the stream opens.
 [2026-08-09] Regeluppdat + docs-freshness scans (#1417) built as local loop skills with due-date self-gating, not cloud crons: cloud routines were retired 2026-07-20, and session crons die at 7 days, so weekly/monthly cadence is achieved by loop-ignite running each loop when its run marker says it is due. loop-regeluppdat files tickets only (no auto-fix PRs): regulatory changes touch money math and compliance logic, which .claude/loops.md forbids loops from changing. Docs check diffs the live .md mirror routes against repo-built markdown (exact, canonicalised both sides) instead of diffing the gnubok-website checkout, so it also catches deployed-but-stale and route-404 states.
+[2026-08-10] RC VAT template fix scoped to template-library.ts (applyTemplate + deriveTemplateLinesFromBooking): counterparty/SIE learned patterns already strip fiktiv-moms legs and regenerate them via generateReverseChargeLines with the gross base, so mapping-engine/counterparty paths were already correct and stay untouched.
 [2026-08-10] Receipt hunt cron keeps searchMail=false: the mailbox leg stays manual until its time budget is proven. A sweep of one 172-message mailbox took over 600s while the route's maxDuration is 300, so enabling it nightly would time out mid-run. Flip both this flag and RECEIPT_HUNT_COMPANY_IDS together once the per-company budget is measured.