* feat(server): add ACP base provider with Claude ACP integration
Implement a generic Agent Client Protocol (ACP) base provider that any
ACP-compatible agent can extend with minimal code. Includes a concrete
Claude ACP implementation via @agentclientprotocol/claude-agent-acp
with full parity to the existing Claude Code provider.
The base handles subprocess lifecycle, streaming translation, permission
bridging, terminal/fs callbacks, listModels, loadSession/resume, and
mode/model management. The concrete class only specifies the command,
modes, and availability check.
* fix: update lockfile signatures and Nix hash
* feat: add Copilot ACP provider, eliminate hardcoded provider unions, fix ACP streaming bugs
Add Copilot as an ACP provider (copilot --acp), with real modes and models
discovered from the ACP server. Fix two ACP base bugs: duplicate assistant
text (emit deltas not cumulative) and idle→running→stuck (fire-and-return
startTurn). Replace all hardcoded provider string unions with string/manifest-
derived values so adding a provider only requires: impl class, manifest entry,
registry factory, icon, and E2E config. Add provider docs and Copilot icon.
* fix: update lockfile signatures and Nix hash
* feat(app): add OpenCode provider icon
---------
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
