Config Directory Cleanup Design

Context

After PR #59 (refactor/env-cleanup) removed env-var-based checker/notify settings from config/settings.py, the config/ directory is leaner but still has structural and coverage gaps:

0% coverage on asgi.py and wsgi.py
96% coverage on settings.py (missing RuntimeError branch on line 36)
94% coverage on env.py (missing dev-env branch)
No _tests/ directory — zero dedicated tests for any config module
140-line admin.py mixes admin site config with dashboard query logic

Design

1. Extract Dashboard Logic

Move prettify_json() and _get_dashboard_context() from config/admin.py into a new config/dashboard.py. Rename _get_dashboard_context to get_dashboard_context (public API).

config/admin.py becomes a thin wrapper that imports and delegates.

2. Test Coverage

Create config/_tests/ with:

File	Covers
`test_settings.py`	Missing `DJANGO_SECRET_KEY` raises `RuntimeError`
`test_env.py`	`load_env()` paths, `_should_load_dev_env()` with `DJANGO_ENV=dev`
`test_entrypoints.py`	`asgi.py` and `wsgi.py` export callable `application`
`test_dashboard.py`	`get_dashboard_context()` keys, `prettify_json()` output
`test_admin.py`	`MonitoringAdminSite` delegates to `get_dashboard_context`

Target: 100% branch coverage for all config/ files.

3. No Changes To

Settings values or comments
.env.sample
celery.py, urls.py, apps.py, __init__.py