feat: add common utilities and feedback handling scripts

- Introduced common.js for shared functions including API calls, error reporting, and UI helpers.
- Implemented feedback.js for the feedback reporting page, including form handling and displaying feedback status.
- Added layout.js for managing galaxy and section layouts in the visualization.
- Created login.js for user authentication with session management.
- Developed search.js for term searching based on user input and synonyms.
- Implemented signup.js for user registration with validation and immediate login.

tests/conftest.py

@@ -0,0 +1,43 @@
+import json
+import os
+import sys
+from pathlib import Path
+
+import pytest
+
+ROOT = Path(__file__).resolve().parent.parent
+sys.path.insert(0, str(ROOT))
+os.environ["ATLAS_OWNER_PASSWORD"] = "owner-pass"
+
+
+@pytest.fixture()
+def client(tmp_path, monkeypatch):
+    from fastapi.testclient import TestClient
+
+    from server import db
+    monkeypatch.setattr(db, "DB_PATH", tmp_path / "test.db")
+    db._local.__dict__.clear()
+    from server import app as app_module
+    app_module._hits.clear()
+    with TestClient(app_module.app) as c:
+        yield c
+    db._local.__dict__.clear()
+
+
+@pytest.fixture()
+def admin(client):
+    r = client.post("/api/admin/login", json={"username": "professor", "password": "owner-pass"})
+    assert r.status_code == 200
+    return client
+
+
+@pytest.fixture(scope="session")
+def atlas():
+    return json.loads((ROOT / "data" / "atlas.json").read_text())
+
+
+@pytest.fixture()
+def owner(client):
+    r = client.post("/api/admin/login", json={"username": "professor", "password": "owner-pass"})
+    assert r.status_code == 200 and r.json()["role"] == "owner"
+    return client