feat: extract reusable dev/CI tools from GRM into devx package

Port core modules (config, exceptions, i18n, api_clients, gitea_cli),
14 CI scripts, 6 dev tools, 5 molecule tools, CLI entry point, workflows,
Makefile, tests (784 tests, 100% coverage), and documentation from GRM.

The devx package is published to the Gitea PyPI registry and consumed
by GRM, infra, and other oblachno-oss projects as a pip dependency.

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Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

tests/unit/test_platforms.py

@@ -0,0 +1,25 @@
+"""Unit tests for scripts/ci/platforms.py."""
+
+from devx.molecule.platforms import PLATFORMS
+
+
+class TestPlatforms:
+    def test_platforms_not_empty(self) -> None:
+        assert len(PLATFORMS) >= 4
+
+    def test_each_platform_has_required_keys(self) -> None:
+        for p in PLATFORMS:
+            assert "name" in p
+            assert "image" in p
+            assert "command" in p
+
+    def test_platform_names_unique(self) -> None:
+        names = [p["name"] for p in PLATFORMS]
+        assert len(names) == len(set(names))
+
+    def test_known_platforms_present(self) -> None:
+        names = {p["name"] for p in PLATFORMS}
+        assert "ubuntu-2204" in names
+        assert "ubuntu-2404" in names
+        assert "debian-12" in names
+        assert "archlinux" in names