fix(inbox): carry the matched transaction amount into manual booking (#1546)

PR #1524 swapped the matched-state "Bokfor manuellt" path from
BookDirectlyDialog to EditKonteringDialog, which is seeded only from the
booking proposal. An unknown supplier has no proposal, so the dialog
opened with two blank rows and no amount at all: on a foreign-currency
invoice the SEK figure then existed nowhere on screen (user-reported
regression, 2026-08-12).

suggest-booking now returns, on every empty-proposal branch (no_mapping,
currency_unsupported, engine failure), the matched bank row's SEK amount
and date plus a balanced two-row skeleton: the settlement account on one
side, a blank cost row on the other, mirroring what buildPrefillLines
seeded before the swap. The SEK amount goes through
resolveSekAmountOrNull, so a foreign row with no honest kronor figure
still opens blank rather than relabeling EUR as SEK. The dialog also
shows the matched transaction's amount and date beside the title, and
empty proposals now carry the bank date so the entry no longer falls
back to the document date.

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

messages/en.json

@@ -3065,6 +3065,7 @@
     "hunt_reading": "Reading {mailboxes}",
     "hunt_progress": "pass {pass} · {found} fetched",
     "dialog_no_document": "No document",
+    "dialog_matched_transaction": "Matched transaction",
     "sources_one": "{count} source",
     "sources_many": "{count} sources",
     "source_needs_reconnect": "{address} needs reconnecting",

messages/sv.json

@@ -3065,6 +3065,7 @@
     "hunt_reading": "Läser {mailboxes}",
     "hunt_progress": "omgång {pass} · {found} hämtade",
     "dialog_no_document": "Ingen handling",
+    "dialog_matched_transaction": "Matchad transaktion",
     "sources_one": "{count} källa",
     "sources_many": "{count} källor",
     "source_needs_reconnect": "{address} behöver återanslutas",