feat: add /add-ollama-provider skill and docs/ollama.md

Adds a new operational skill that routes any agent group to a local
Ollama instance instead of the Anthropic API. Ollama speaks the
Anthropic /v1/messages endpoint natively, so no new provider code is
needed — just env var overrides and a model setting in the shared
settings file.

The skill also documents and applies two prerequisite source changes:
- ContainerConfig gains env and blockedHosts fields (container-config.ts)
- container-runner wires those fields as -e and --add-host Docker flags
- Dockerfile home dir set to chmod 777 so containers running as the
  host uid can write ~/.claude config (discovered during implementation)

docs/ollama.md covers the architecture, OneCLI proxy bypass rationale,
network isolation via blockedHosts, model selection tradeoffs for Apple
Silicon, and revert instructions.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/ollama.md

@@ -0,0 +1,88 @@
+# Running Agents on Local Ollama
+
+NanoClaw agents can be routed to a local [Ollama](https://ollama.com) instance instead of the Anthropic API. This cuts API costs to zero and keeps all inference on your hardware.
+
+## How It Works
+
+Ollama exposes an Anthropic-compatible `/v1/messages` endpoint. The Claude Code CLI (which runs inside agent containers) uses the Anthropic SDK, which reads `ANTHROPIC_BASE_URL` to find the API host. Pointing that variable at Ollama is all that's needed — no new provider code, no changes to the agent runtime.
+
+```
+┌─────────────────────────────┐
+│  Agent container            │
+│                             │
+│  Claude Code CLI            │
+│    ↓ ANTHROPIC_BASE_URL     │
+│    http://host.docker.      │      ┌──────────────────┐
+│    internal:11434    ───────┼─────▶│  Ollama :11434   │
+│                             │      │  gemma4:latest   │
+└─────────────────────────────┘      └──────────────────┘
+```
+
+`host.docker.internal` is Docker's magic hostname that resolves to the host machine from inside a container — so Ollama running on your Mac or Linux box is reachable at that address.
+
+## The OneCLI Complication
+
+NanoClaw normally runs API calls through an OneCLI HTTPS proxy that injects real credentials in place of a placeholder key. When redirecting to Ollama you need to bypass that proxy so requests go direct. Two env vars handle this:
+
+- `NO_PROXY=host.docker.internal` — tells the Anthropic SDK's HTTP client to skip the proxy for that hostname
+- `no_proxy=host.docker.internal` — lowercase variant for tools that check the lowercase form
+
+Both are set in the agent group's `container.json` alongside `ANTHROPIC_BASE_URL`.
+
+## Network Isolation
+
+Setting `ANTHROPIC_BASE_URL` redirects requests but doesn't prevent a misconfigured agent from accidentally reaching `api.anthropic.com` directly. The `blockedHosts` field in `container.json` adds a Docker `--add-host` flag that resolves the domain to `0.0.0.0`, making it physically unreachable from inside the container:
+
+```json
+"blockedHosts": ["api.anthropic.com"]
+```
+
+With this in place, even if the model setting drifts back to a Claude model name, the API call will fail immediately rather than silently billing your account.
+
+## Model Selection
+
+The Claude Code CLI reads its model from `~/.claude/settings.json` inside the container, which NanoClaw bind-mounts from `data/v2-sessions/<agent-group-id>/.claude-shared/settings.json`. Set `"model": "gemma4:latest"` (or whatever Ollama model you've pulled) there. Use the exact name from `ollama list`.
+
+Model selection considerations for Apple Silicon:
+
+| Model | Size | Quality | Speed (M4 Pro) |
+|-------|------|---------|----------------|
+| `gemma4:latest` | 12B | Good general-purpose | Fast |
+| `qwen3-coder:latest` | 32B | Excellent for coding tasks | Moderate |
+| `llama3.2:latest` | 3B | Basic | Very fast |
+
+The agent uses tool calls extensively (read/write files, shell commands). Models that support tool use reliably work best. Gemma 4 and Qwen 3 Coder both handle structured tool calls well.
+
+## What Changes at the Code Level
+
+Three files need to support this feature. See `/add-ollama-provider` for the exact changes.
+
+**`src/container-config.ts`** — `ContainerConfig` interface needs `env` and `blockedHosts` fields so the per-group JSON can carry them.
+
+**`src/container-runner.ts`** — At container spawn time, `env` entries become `-e KEY=VAL` Docker flags (applied after OneCLI's injected vars so they win), and `blockedHosts` entries become `--add-host HOST:0.0.0.0` flags.
+
+**`container/Dockerfile`** — The container runs as the host user's uid (e.g. 501 on macOS), not as the `node` user (uid 1000). The home directory must be `chmod 777` so any uid can write `~/.claude.json` and `~/.claude/settings.json`.
+
+## Tradeoffs
+
+| | Ollama (local) | Anthropic API |
+|---|---|---|
+| Cost | Free | Pay-per-token |
+| Privacy | Fully local | Data sent to Anthropic |
+| Model quality | Good (open-weight) | Excellent (Claude) |
+| Cold start | 5–30s (model load) | ~1s |
+| Context window | Varies by model | 200k tokens (Sonnet) |
+| Tool use reliability | Good (large models) | Excellent |
+| Hardware req. | 16GB+ RAM | None |
+
+For personal automation on capable hardware, the tradeoff favors local. For complex multi-step tasks requiring large context or high reliability, Claude is still ahead.
+
+## Reverting to Claude
+
+Remove the `env` and `blockedHosts` keys from `groups/<folder>/container.json`, remove `"model"` from the shared settings file, and restart the service. No rebuild needed.
+
+## See Also
+
+- `/add-ollama-provider` — step-by-step skill to configure any agent group for Ollama
+- [Ollama Anthropic compatibility docs](https://ollama.com/blog/openai-compatibility) — upstream docs on the API bridge
+- `docs/architecture.md` — how the container spawn and env injection pipeline works