feat(tests): add unit and integration test suite (node:test)

Adds 215 tests across three tiers using node:test + node:assert/strict
(no new test framework dependencies):

- test/tools/ — middleware and utility tests (token, hash, authenticate,
  jsonBody, convertError, validators)
- test/shared/ — DbInterface/BackendDbInterface contract suites reusable
  across backends (users, abodes, residents, apikeys, sessions, auth)
- test/backends/sqlite/ — SQLite-private tests (sql builder, WrappedDb,
  migrator) + shared suites via SqliteInterface
- test/backends/api/ — ApiInterface unit tests + shared suites via a
  live Koa server backed by SQLite

Also fixes four bugs uncovered by the tests:
- ApiInterface: path params leaked into query string (slice(1) fix)
- ApiInterface: calling res.json() on 204 No Content responses
- SqliteInterface.updateResident: missing comma in SET clause
- WrappedBetterSqlite3Db: readonly:undefined rejected by better-sqlite3

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

test/shared/abodes.ts

@@ -0,0 +1,109 @@
+import { describe, it, before, after } from "node:test";
+import assert from "node:assert/strict";
+import type { DbInterface } from "../../src/db/types/DbInterface.js";
+import { NotFoundAbodeError, InvalidAbodeError } from "../../src/db/types/errors.js";
+import { hashPassword } from "../../src/util/hash.js";
+
+export function runAbodeTests(
+  name: string,
+  getDb: () => Promise<{ db: DbInterface; close(): void }>
+): void {
+  describe(`${name}: abodes`, async () => {
+    let db: DbInterface;
+    let close: () => void;
+    let ctxUid: string;
+
+    before(async () => {
+      ({ db, close } = await getDb());
+      const pw = await hashPassword("abode-ctx");
+      const user = await db.createUser({
+        email: `abode-ctx-${Date.now()}@test.example`,
+        name: "Abode Ctx User",
+        password: pw,
+        flags: {},
+      });
+      ctxUid = user.uid;
+    });
+
+    after(() => close());
+
+    it("createAbode returns an Abode with expected fields", async () => {
+      const abode = await db.createAbode({ name: "Test Abode" }, { uid: ctxUid });
+      assert.ok(abode.aid, "has aid");
+      assert.equal(abode.name, "Test Abode");
+      assert.ok(abode.created_at);
+      assert.ok(abode.updated_at);
+    });
+
+    it("getAbodeById returns the created abode", async () => {
+      const created = await db.createAbode({ name: "ById Abode" }, { uid: ctxUid });
+      const found = await db.getAbodeById(created.aid);
+      assert.equal(found.aid, created.aid);
+      assert.equal(found.name, "ById Abode");
+    });
+
+    it("getAbodeById throws NotFoundAbodeError for unknown aid", async () => {
+      await assert.rejects(
+        () => db.getAbodeById("00000000-0000-0000-0000-000000000000"),
+        (err) => {
+          assert.ok(err instanceof NotFoundAbodeError);
+          return true;
+        }
+      );
+    });
+
+    it("listAbodes includes the created abode", async () => {
+      const created = await db.createAbode(
+        { name: `Listed Abode ${Date.now()}` },
+        { uid: ctxUid }
+      );
+      const abodes = await db.listAbodes();
+      assert.ok(Array.isArray(abodes));
+      const found = abodes.find((a) => a.aid === created.aid);
+      assert.ok(found, "created abode appears in listAbodes");
+    });
+
+    it("updateAbode updates the name", async () => {
+      const created = await db.createAbode({ name: "Before" }, { uid: ctxUid });
+      const updated = await db.updateAbode(
+        { aid: created.aid, name: "After" },
+        { uid: ctxUid }
+      );
+      assert.equal(updated.aid, created.aid);
+      assert.equal(updated.name, "After");
+    });
+
+    it("updateAbode with no fields throws InvalidAbodeError", async () => {
+      const created = await db.createAbode({ name: "No Update" }, { uid: ctxUid });
+      await assert.rejects(
+        () => db.updateAbode({ aid: created.aid }, { uid: ctxUid }),
+        (err) => {
+          assert.ok(err instanceof InvalidAbodeError);
+          return true;
+        }
+      );
+    });
+
+    it("deleteAbodeById removes the abode", async () => {
+      const created = await db.createAbode({ name: "To Delete" }, { uid: ctxUid });
+      await db.deleteAbodeById(created.aid);
+      await assert.rejects(
+        () => db.getAbodeById(created.aid),
+        (err) => {
+          assert.ok(err instanceof NotFoundAbodeError);
+          return true;
+        }
+      );
+    });
+
+    it("deleteAbodeById throws NotFoundAbodeError for unknown aid", async () => {
+      await assert.rejects(
+        () => db.deleteAbodeById("00000000-0000-0000-0000-000000000000"),
+        (err) => {
+          assert.ok(err instanceof NotFoundAbodeError);
+          return true;
+        }
+      );
+    });
+  });
+}