chore: adopt the NAPALM driver standard

- CI moves to .gitea/workflows/ci.yml and calls the shared driver workflow
  of NAPALM/driver-standard; .github/ is gone.
- setuptools>=77 with the SPDX license string, no License classifier,
  Python 3.10-3.13 classifiers, napalm-device-types>=4.21.1, a dev extra
  with floors, links to git.netork.io, LICENSE file, py.typed.
- CHANGELOG.md in Keep-a-Changelog form; README names Python 3.10, the
  Gitea clone URL and the new CI.
- mypy strict for the package; exempt for now (52 errors): ha, listening,
  opnsense, ospf_mixin, ping_mixin, port_forwards, resolver_mixin.
  Recorded in the quality baseline with the long and complex functions,
  the 3100-line opnsense.py and one unannotated public method.
- Coverage floor 79 % (measured 79.20 %).

.gitea/workflows/ci.yml

@@ -0,0 +1,15 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+    tags: ["v*"]
+  pull_request:
+
+jobs:
+  driver:
+    uses: NAPALM/driver-standard/.gitea/workflows/driver.yml@main
+    with:
+      standard-ref: main
+    secrets:
+      PYPI_TOKEN: ${{ secrets.PYPI_TOKEN }}