feat(picooraclaw): add OrcaRouter as a first-class provider

[martinzudergaming-a11y]

Summary

PicoOraClaw already lets users "swap to any provider" from ~/.picooraclaw/config.json — OpenRouter, Groq, Ollama, and friends each have a named entry in the providers schema. OrcaRouter is an OpenAI-compatible AI gateway built for both models and agents. Like OpenRouter, it exposes a provider/model namespace across many models — but it also combines adaptive routing, automatic failover, zero-markup inference, observability, guardrails, and agent-tool governance behind the same endpoint. Adding orcarouter as a first-class provider means PicoOraClaw users can use that stack directly, without treating OrcaRouter as an anonymous custom base URL.

It also runs gateway-level, zero-trust security for AI agents on the same endpoint — screening every prompt/response and governing every tool call on a default-deny basis, with no application code changes.

Changes

• Register orcarouter in ProvidersConfig / DefaultConfig (pkg/config/config.go), mirroring the openrouter entry.
• Route provider: "orcarouter" and orcarouter/... model prefixes to https://api.orcarouter.ai/v1 in CreateProvider (pkg/providers/http_provider.go), including the fallback model-prefix detection.
• Include OrcaRouter in GetAPIKey / GetAPIBase so gateway-level key/base resolution works when it is the configured backend.
• Support migrating orcarouter from OpenClaw configs and preserving it across config merges (pkg/migrate/config.go).
• Document the provider in README.md, config/config.example.json, the init key hint in cmd/picooraclaw/main.go, and workspace/IDENTITY.md.
• Add unit tests for the default config, migration mapping, full migration, and config merge.

Verification

• go build ./... passes.
• go test ./... passes (14 packages, 0 failures).
• Live test: a config with provider: "orcarouter" and model orcarouter/fusion-flash resolves through CreateProvider and completes a real chat/completions round-trip against https://api.orcarouter.ai/v1 (finish_reason stop, valid content).

Discord: discord.gg/YEubt8enRA · X: https://x.com/OrcaRouter

I'm an engineer on the OrcaRouter team.

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