Crate: agent-doc-config

Spec

Defines Config: global user configuration loaded from ~/.config/agent-doc/config.toml (or $XDG_CONFIG_HOME/agent-doc/config.toml). Fields: default_agent, agents map, agent_args, claude_args, codex_args, opencode_args (harness aliases), execution_mode, terminal.
Defines AgentConfig: per-named-agent settings (command, args, result_path, session_path).
Defines TerminalConfig: command template for launching an external terminal; supports {tmux_command} substitution.
Defines ExecutionMode enum: Hybrid (default — first doc direct, rest subagent), Parallel (always subagent), Sequential (fully serial).
load() reads and parses the global config file; returns Config::default() when the file is absent. Propagates I/O and parse errors via anyhow::Result.
Project-level configuration types live in agent-doc-frontmatter; file-backed helpers live in agent-doc-project-config-io.

Never panics on missing config: load() returns defaults when the file is absent.