Add uv and a rootless Docker runtime on NixOS hosts

uv joins the CLI package list. Docker's daemon is now actually managed
on NixOS hosts too, in rootless mode (per-user systemd service, no
docker-group root-equivalent access), rather than leaving the runtime
entirely externally-managed as before -- the already-installed docker
CLI picks it up automatically via DOCKER_HOST. This is a documented,
narrow exception to developer-environment's client-only tools policy;
kubectl and awscli2 remain unaffected.

Archives add-uv-and-docker-runtime and syncs the new container-runtime
capability plus the narrowed developer-environment requirement into
the main specs.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01HngxrvqEzq8oBEBDtrYJyB

1 files changed, 12 insertions, 0 deletions

diff --git a/openspec/changes/archive/2026-09-24-add-uv-and-docker-runtime/specs/developer-environment/spec.md b/openspec/changes/archive/2026-09-24-add-uv-and-docker-runtime/specs/developer-environment/spec.md
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+++ b/openspec/changes/archive/2026-09-24-add-uv-and-docker-runtime/specs/developer-environment/spec.md
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+## MODIFIED Requirements
+
+### Requirement: Container and cloud tools are client-only
+Container and cloud-related packages provisioned by this capability SHALL provide client/CLI functionality only; they SHALL NOT attempt to provide or manage the underlying runtime or service (e.g. a Kubernetes cluster or cloud account), with one exception: Docker's runtime is managed on NixOS hosts by the separate `container-runtime` capability. Outside of NixOS hosts, and for every other tool (`kubectl`, `awscli2`), no corresponding runtime or account is installed or managed.
+
+#### Scenario: No runtime is installed or managed
+- **WHEN** a container or cloud CLI tool other than Docker is provisioned by the shared home profile
+- **THEN** no corresponding daemon, virtual machine, or account configuration is installed or managed by this capability — the tool simply connects to whatever runtime or account is already configured on the system
+
+#### Scenario: Docker's runtime is the documented exception on NixOS
+- **WHEN** the Docker CLI is provisioned by the shared home profile on a NixOS host built from this flake's shared system module
+- **THEN** a Docker runtime is available via the separate `container-runtime` capability, rather than being left entirely unmanaged