refactor: rename the application package to docsgpt

The backend import package is now docsgpt, the name it will carry on PyPI;
application was far too generic to install into anyone's site-packages.
git mv plus a mechanical rewrite of every import, dotted string and path
reference: 734 Python files, the compose files, Dockerfile, workflows, docs,
setup scripts, devcontainer, k8s manifests, vscode config, pytest and coverage
config, .gitignore. Behaviour is unchanged.

Kept for one release:
- A top-level application package whose meta-path finder resolves
  application.x.y to the already-imported docsgpt.x.y object, so old imports
  and entry points (celery -A application.app.celery,
  uvicorn application.asgi:asgi_app) keep working with a FutureWarning.
- Celery registers every application.* task name as an alias of its
  docsgpt.* task on start-up, so messages queued by the previous release still
  run. The redbeat key prefix moves to redbeat:docsgpt:v2: so schedule entries
  the previous release wrote are left unread instead of firing twice.

The backend image builds from the repository root (docker build -f
docsgpt/Dockerfile .) so it can ship the alias package; a root .dockerignore
allow-lists docsgpt/ and application/ and keeps caches, local data, .env
files, the sample index files and the Dockerfile out. Compose and the image
workflows point at the new context.

tests/integration/_drain_harness_app.py

@@ -3,7 +3,7 @@
 Mirrors production (a Flask SSE generator behind a2wsgi's thread pool) without
 Postgres/Redis. ``/sse`` holds the connection open like an idle subscriber;
 ``DRAIN_HARNESS_COOPERATIVE=1`` makes it poll the real
-``application.core.shutdown.is_shutting_down`` flag (the fix), else it
+``docsgpt.core.shutdown.is_shutting_down`` flag (the fix), else it
 reproduces the pre-fix hang.
 """
 
@@ -17,7 +17,7 @@ from flask import Flask, Response
 from starlette.applications import Starlette
 from starlette.routing import Mount
 
-from application.core.shutdown import is_shutting_down
+from docsgpt.core.shutdown import is_shutting_down
 
 _COOPERATIVE = os.environ.get("DRAIN_HARNESS_COOPERATIVE") == "1"
 _POLL_SECONDS = 1.0

tests/integration/conftest.py

@@ -30,7 +30,7 @@ from __future__ import annotations
 import pytest
 from sqlalchemy import Engine, create_engine, text
 
-from application.core.settings import settings
+from docsgpt.core.settings import settings
 
 
 @pytest.fixture(scope="session")

tests/integration/test_scim.py

@@ -19,10 +19,10 @@ from unittest.mock import patch
 import pytest
 from sqlalchemy import text
 
-from application.core.settings import settings
-from application.storage.db.repositories.auth_events import AuthEventsRepository
-from application.storage.db.repositories.users import UsersRepository
-from application.storage.db.session import db_readonly, db_session
+from docsgpt.core.settings import settings
+from docsgpt.storage.db.repositories.auth_events import AuthEventsRepository
+from docsgpt.storage.db.repositories.users import UsersRepository
+from docsgpt.storage.db.session import db_readonly, db_session
 
 SCIM_TOKEN = "scim-test-token"
 AUTH = {"Authorization": f"Bearer {SCIM_TOKEN}"}
@@ -42,7 +42,7 @@ pytestmark = [
 @pytest.fixture(scope="module")
 def app():
     """Real Flask app; /scim/ paths bypass JWT auth so no handle_auth patching is needed."""
-    from application.app import app as flask_app
+    from docsgpt.app import app as flask_app
 
     flask_app.config["TESTING"] = True
     return flask_app
@@ -58,7 +58,7 @@ def scim_env(monkeypatch):
     """Enable SCIM on the settings singleton and stub the Redis denylist."""
     monkeypatch.setattr(settings, "SCIM_ENABLED", True)
     monkeypatch.setattr(settings, "SCIM_TOKEN", SCIM_TOKEN)
-    with patch("application.api.scim.routes.deny_user") as deny_user_mock:
+    with patch("docsgpt.api.scim.routes.deny_user") as deny_user_mock:
         yield SimpleNamespace(deny_user=deny_user_mock)
 
 

tests/integration/test_users_repository.py

@@ -23,7 +23,7 @@ from __future__ import annotations
 
 import pytest
 
-from application.storage.db.repositories.users import UsersRepository
+from docsgpt.storage.db.repositories.users import UsersRepository
 
 
 @pytest.fixture

tests/integration/test_worker_drain_e2e.py

@@ -31,7 +31,7 @@ _GUNICORN = Path(sys.executable).with_name("gunicorn")
 _MAX_REQUESTS = "5"
 _TIMEOUT = "6"            # gunicorn worker-timeout watchdog
 _GRACEFUL = "30"          # gunicorn --graceful-timeout (not the lever; here for parity)
-_GUNICORN_CONF = _ROOT / "application" / "gunicorn_conf.py"
+_GUNICORN_CONF = _ROOT / "docsgpt" / "gunicorn_conf.py"
 
 pytestmark.append(
     pytest.mark.skipif(not _GUNICORN.exists(), reason="gunicorn binary not found")
@@ -177,7 +177,7 @@ def test_bounded_drain_worker_exits_cleanly_with_held_sse(tmp_path):
     log = tmp_path / "fixed.log"
     base = f"http://127.0.0.1:{port}"
     proc, fh = _boot(
-        "application.gunicorn_worker.BoundedDrainUvicornWorker",
+        "docsgpt.gunicorn_worker.BoundedDrainUvicornWorker",
         port,
         log,
         {"DRAIN_HARNESS_COOPERATIVE": "1"},

tests/integration/test_workflows.py

@@ -27,7 +27,7 @@ from jose import jwt
 @pytest.fixture(scope="module")
 def app():
     """Create the real Flask app (connects to real Postgres)."""
-    from application.app import app as flask_app
+    from docsgpt.app import app as flask_app
     flask_app.config["TESTING"] = True
     return flask_app
 
@@ -40,7 +40,7 @@ def client(app):
     injected; otherwise the backend already returns {"sub": "local"}
     for every request so no token is needed.
     """
-    from application.core.settings import settings
+    from docsgpt.core.settings import settings
 
     c = app.test_client()
     if settings.AUTH_TYPE in ("simple_jwt", "session_jwt"):