Bake 0.4.0

Bake 0.4.0 is a new native agent, bake, written in Rust. This first release is for Linux.

• Linux first. Releases are published for Linux x86_64 and arm64 with glibc 2.34 or newer. macOS and Windows support is coming in a later 0.4 release; until then the installers stop on those platforms before they download anything, and on Windows you can install Bake inside WSL.
• A separate install. curl -fsSL https://bake.justar.dev/install.sh | sh installs bake into ~/.local/share/bake-native and links it into ~/.local/bin; it needs no Node or Bun. It does not upgrade or migrate a Bake 0.3 install: it takes over a 0.3 bake command and records how to restore it (--uninstall-links), leaves 0.3's dsh command alone, and a 0.3 bake update stays on 0.3.
• The end of 0.3. Bake 0.3, the TypeScript agent, receives no further bug or security fixes, and its dsh command, profile, and package aliases retire with it (D10 and D13). Each BAKE_* environment setting still falls back to its DSH_* name.
• Your Bake home carries over. bake uses ~/.bake (BAKE_HOME, then DSH_HOME) and reads 0.3's CLIProxyAPI route, key, and default model without changing them. Sessions are saved in pi's session format; 0.3 session logs are not opened.
• What it does: interactive sessions, fullscreen or inline, where you can steer or stop a turn; model, thinking, session, tree, fork, compaction, and settings commands; /login for a CLIProxyAPI account and models.json for any OpenAI- or Anthropic-compatible provider; sandboxed bash, file, search, web, and code-mode tools under permission presets and approvals; background shells, and opt-in subagents and reminders; AGENTS.md context files, skills, prompt templates, MCP servers, command hooks, and Wasm plugins that can veto tool calls; print, JSON, and RPC modes; and bake update with --rollback. bake docs describes each.
• Not in 0.4.0: goals and the task router, MCP OAuth, MCP resource subscriptions and prompts, and further slash commands come in later releases.