Contracts for 14 default categories and the category suggestion (UX-3, UX-8)

- contracts/schema/migrations/0002_categories_v2.sql: server migration 0002 rebuilds categories with the
  14-key default_key CHECK, inserts housing, insurance, children and fees with server_versions taken from
  the global sequence, sets schema_version 2. server-v1.sql unchanged.
- contracts/category-keywords.csv: the keyword table of the suggestion (148 entries, from docs/ux).
- contracts/test-vectors/suggest_category.json: 65 Kotlin-only cases of CS-4 to CS-6.
- contracts/examples/E-1-health: schema_version 2.
- tools/contracts-check.py: reference suggestCategory, keyword-table checks, 0002 load checks on a fresh
  and an in-use database, plain icon/color check, new icon and colour tokens.
- android/domain: suggestCategory (CS-4 to CS-6, code points, platform NFC and categories through
  UnicodeText), vector runner for suggest_category, eight vector files.
- server/crates/kvitt-domain/tests/vectors.rs: suggest_category is Kotlin-only.

The OpenAPI DefaultCategoryKey extension and the two new category examples are held back until the
server's wire types know the new keys (M12b).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TQd3pEP9UeN2uifbHknQ7B

contracts/category-keywords.csv

@@ -0,0 +1,149 @@
+keyword,match,default_key,source
+barn,prefix,children,data
+blöjor,token,children,curated
+fritids,token,children,curated
+förskol,prefix,children,data
+leksak,prefix,children,curated
+napp,prefix,children,data
+resevagn,token,children,data
+bio,token,entertainment,data
+entre,token,entertainment,data
+entré,token,entertainment,data
+filmstaden,token,entertainment,curated
+karaoke,token,entertainment,data
+konsert,prefix,entertainment,data
+museet,token,entertainment,curated
+museum,token,entertainment,data
+netflix,token,entertainment,curated
+padel,token,entertainment,curated
+spotify,token,entertainment,data
+teater,prefix,entertainment,curated
+bankavgift,token,fees,curated
+kvarskatt,token,fees,curated
+ränteåterbäring,token,fees,data
+skatt,token,fees,curated
+skatteverket,token,fees,curated
+alkohol,token,groceries,data
+bondens marknad,phrase,groceries,data
+bröd,token,groceries,data
+bubbel,token,groceries,data
+city gross,phrase,groceries,curated
+coop,token,groceries,data
+frukt,token,groceries,curated
+grönsaker,token,groceries,data
+handling,prefix,groceries,data
+hemköp,token,groceries,data
+ica,token,groceries,data
+julmat,token,groceries,data
+lidl,token,groceries,curated
+livs,token,groceries,data
+livsmedel,prefix,groceries,curated
+mat,token,groceries,data
+mjölk,token,groceries,data
+netto,token,groceries,data
+ost,token,groceries,data
+snacks,token,groceries,data
+storhandling,token,groceries,data
+systembolag,prefix,groceries,data
+systemet,token,groceries,data
+willys,token,groceries,data
+apotek,prefix,health,data
+kry,token,health,curated
+läkare,token,health,curated
+medicin,prefix,health,curated
+sjukhus,token,health,curated
+tandläkare,token,health,curated
+tandvård,token,health,curated
+vårdcentral,token,health,curated
+bauhaus,token,home,data
+byggmax,token,home,curated
+clas ohlson,phrase,home,data
+elgiganten,token,home,curated
+färg,token,home,data
+garderob,prefix,home,data
+gardin,prefix,home,data
+hylla,token,home,data
+ikea,token,home,data
+jysk,token,home,curated
+lamp,prefix,home,data
+möbler,token,home,curated
+ohlson,token,home,data
+rusta,token,home,data
+amortering,prefix,housing,curated
+avgift,token,housing,data
+bolån,token,housing,curated
+brf,token,housing,data
+hyra,token,housing,data
+lgh,token,housing,data
+ränta,token,housing,data
+barnförsäkring,token,insurance,curated
+bilförsäkring,token,insurance,curated
+folksam,token,insurance,curated
+försäkring,prefix,insurance,data
+hemförsäkring,token,insurance,data
+länsförsäkringar,token,insurance,curated
+trygg hansa,phrase,insurance,curated
+bagel,prefix,restaurants,data
+bageri,prefix,restaurants,data
+bar,token,restaurants,curated
+burger king,phrase,restaurants,curated
+cafe,token,restaurants,curated
+café,token,restaurants,data
+dumplings,token,restaurants,data
+fika,prefix,restaurants,data
+foodora,token,restaurants,curated
+glass,token,restaurants,data
+hamburgare,token,restaurants,curated
+kaffe,token,restaurants,data
+kebab,token,restaurants,data
+lunch,token,restaurants,data
+max,token,restaurants,data
+mcdonalds,token,restaurants,curated
+middag,token,restaurants,data
+pizz,prefix,restaurants,data
+ramen,token,restaurants,data
+restaurang,prefix,restaurants,curated
+seml,prefix,restaurants,data
+streetfood,token,restaurants,data
+sushi,token,restaurants,data
+thai,token,restaurants,data
+uber eats,phrase,restaurants,curated
+amazon,token,shopping,curated
+h&m,token,shopping,curated
+kappahl,token,shopping,curated
+lindex,token,shopping,curated
+present,prefix,shopping,data
+skor,token,shopping,curated
+stadium,token,shopping,curated
+zalando,token,shopping,curated
+bensin,token,transport,curated
+bil,token,transport,data
+buss,prefix,transport,curated
+flygbuss,token,transport,curated
+färj,prefix,transport,data
+laddning,prefix,transport,data
+okq8,token,transport,curated
+parkering,prefix,transport,data
+preem,token,transport,curated
+sj,token,transport,curated
+sl,token,transport,curated
+tanka,token,transport,curated
+taxi,token,transport,data
+trängselskatt,token,transport,curated
+tåg,token,transport,data
+uber,token,transport,curated
+airbnb,token,travel,data
+boende,token,travel,data
+booking,token,travel,curated
+flyg,token,travel,curated
+hotel,token,travel,data
+hotell,token,travel,data
+sas,token,travel,curated
+bredband,token,utilities,curated
+elräkning,token,utilities,curated
+internet,token,utilities,data
+städning,prefix,utilities,curated
+tele2,token,utilities,curated
+telenor,token,utilities,curated
+telia,token,utilities,curated
+vattenfall,token,utilities,curated

contracts/examples/E-1-health/response.json

@@ -1,6 +1,6 @@
 {
   "status": "ok",
   "server_version": "0.1.0",
-  "schema_version": 1,
+  "schema_version": 2,
   "db_ok": true
 }

contracts/schema/migrations/0002_categories_v2.sql

@@ -0,0 +1,64 @@
+-- Kvitt server schema v2: four new default categories (housing, insurance, children, fees). Do not edit; add a new
+-- migration and bump the schema version (SPEC §14.8). Applied on top of server-v1.sql (0001_init.sql).
+--
+-- The default_key CHECK of categories cannot be altered in place in SQLite, so the table is rebuilt: copy the rows
+-- aside, drop the table, recreate it with the new CHECK and copy the rows back, ids and server_version unchanged.
+-- The migration runs inside one transaction (sqlx wraps every migration in one) with foreign_keys = ON (SPEC §8.9).
+-- defer_foreign_keys = ON lets expenses and recurring_templates point at categories while the table is briefly
+-- absent; the deferred check at commit still fails the migration if any reference is left dangling. It resets
+-- itself when the transaction ends. No other table, index or trigger refers to categories by anything but name.
+PRAGMA defer_foreign_keys = ON;
+
+CREATE TABLE categories_v1_copy AS SELECT * FROM categories;
+DROP TABLE categories;
+
+CREATE TABLE categories (
+    id             TEXT PRIMARY KEY NOT NULL,
+    default_key    TEXT UNIQUE CHECK (default_key IS NULL OR default_key IN
+                       ('groceries', 'restaurants', 'home', 'utilities', 'transport',
+                        'travel', 'entertainment', 'health', 'shopping', 'other',
+                        'housing', 'insurance', 'children', 'fees')),
+    name           TEXT CHECK (name IS NULL OR length(name) BETWEEN 1 AND 40),
+    icon           TEXT NOT NULL,
+    color          TEXT NOT NULL,
+    sort_order     INTEGER NOT NULL,
+    created_at     TEXT NOT NULL,
+    updated_at     TEXT NOT NULL,
+    archived_at    TEXT,
+    deleted_at     TEXT,
+    server_version INTEGER NOT NULL UNIQUE,
+    CHECK (name IS NOT NULL OR default_key IS NOT NULL)
+) STRICT;
+
+INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version)
+    SELECT id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version
+    FROM categories_v1_copy;
+DROP TABLE categories_v1_copy;
+
+-- Each new row takes the next server_version from the global sequence, as every server write does (SPEC §14.1), so
+-- phones receive the rows on their next pull whatever their cursor.
+UPDATE sync_sequence SET value = value + 1 WHERE id = 1;
+INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version)
+    SELECT '01920000-0000-7000-8000-000000000011', 'housing', NULL, 'key', 'indigo', 25,
+           '2026-10-18T00:00:00.000Z', '2026-10-18T00:00:00.000Z', NULL, NULL, value
+    FROM sync_sequence WHERE id = 1;
+
+UPDATE sync_sequence SET value = value + 1 WHERE id = 1;
+INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version)
+    SELECT '01920000-0000-7000-8000-000000000012', 'insurance', NULL, 'shield', 'slate', 45,
+           '2026-10-18T00:00:00.000Z', '2026-10-18T00:00:00.000Z', NULL, NULL, value
+    FROM sync_sequence WHERE id = 1;
+
+UPDATE sync_sequence SET value = value + 1 WHERE id = 1;
+INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version)
+    SELECT '01920000-0000-7000-8000-000000000013', 'children', NULL, 'child_care', 'lime', 85,
+           '2026-10-18T00:00:00.000Z', '2026-10-18T00:00:00.000Z', NULL, NULL, value
+    FROM sync_sequence WHERE id = 1;
+
+UPDATE sync_sequence SET value = value + 1 WHERE id = 1;
+INSERT INTO categories (id, default_key, name, icon, color, sort_order, created_at, updated_at, archived_at, deleted_at, server_version)
+    SELECT '01920000-0000-7000-8000-000000000014', 'fees', NULL, 'account_balance', 'amber', 95,
+           '2026-10-18T00:00:00.000Z', '2026-10-18T00:00:00.000Z', NULL, NULL, value
+    FROM sync_sequence WHERE id = 1;
+
+UPDATE meta SET value = '2' WHERE key = 'schema_version';