change(python): move request & pkgbase request routes

Move package request routes and related routes to their
respective routers. In addition, move some utility used
for requests over from `aurweb.packages`.

Introduced routers:
- `aurweb.routers.requests`

Introduced package:
- `aurweb.requests`

Introduced module:
- `aurweb.requests.util`

Changes:
- Moved `aurweb.packages.validate` to `aurweb.pkgbase.validate`
- Moved requests listing & request closure routes to
  `aurweb.routers.requests`
- Moved pkgbase request creation route to `aurweb.routers.pkgbase`
- Moved `get_pkgreq_by_id` from `aurweb.packages.util` to
  `aurweb.requests.util` and fixed its return type hint.

Signed-off-by: Kevin Morris <kevr@0cost.org>

test/test_requests.py

@@ -6,6 +6,7 @@ from logging import DEBUG
 
 import pytest
 
+from fastapi import HTTPException
 from fastapi.testclient import TestClient
 
 from aurweb import asgi, config, db
@@ -15,6 +16,7 @@ from aurweb.models.package_notification import PackageNotification
 from aurweb.models.package_request import ACCEPTED_ID, PENDING_ID, REJECTED_ID
 from aurweb.models.request_type import DELETION_ID, MERGE_ID, ORPHAN_ID
 from aurweb.packages.requests import ClosureFactory
+from aurweb.requests.util import get_pkgreq_by_id
 from aurweb.testing.email import Email
 from aurweb.testing.html import get_errors
 from aurweb.testing.requests import Request
@@ -583,3 +585,8 @@ def test_closure_factory_invalid_reqtype_id():
         automated.get_closure(666, None, None, None, ACCEPTED_ID)
     with pytest.raises(NotImplementedError, match=match):
         automated.get_closure(666, None, None, None, REJECTED_ID)
+
+
+def test_pkgreq_by_id_not_found():
+    with pytest.raises(HTTPException):
+        get_pkgreq_by_id(0)