feat: add household_invites migration (017)

app/db/migrations/017_household_invites.sql

@@ -0,0 +1,10 @@
+-- 017_household_invites.sql
+CREATE TABLE IF NOT EXISTS household_invites (
+    token        TEXT PRIMARY KEY,
+    household_id TEXT NOT NULL,
+    created_by   TEXT NOT NULL,
+    created_at   TEXT NOT NULL DEFAULT (datetime('now')),
+    expires_at   TEXT NOT NULL,
+    used_at      TEXT,
+    used_by      TEXT
+);