Add interactive setup wizard and persistent settings

- Add 7-step setup wizard: database, security, auth, model, embeddings, channels, heartbeat
- Store settings in ~/.ironclaw/settings.json with env var > settings > default priority
- Add OS keychain integration for secrets master key (macOS/Linux)
- Add `ironclaw config` CLI subcommand (list/get/set/reset/path)
- Expand Settings struct with all configuration fields
- Enhanced setup detection to auto-trigger wizard when needed

Co-Authored-By: Claude Opus 4.5 <[email protected]>

src/cli/mod.rs

@@ -3,11 +3,13 @@
 //! Provides subcommands for:
 //! - Running the agent (`run`)
 //! - Interactive setup wizard (`setup`)
+//! - Managing configuration (`config list`, `config get`, `config set`)
 //! - Managing WASM tools (`tool install`, `tool list`, `tool remove`)
-//! - Managing secrets (`secret set`, `secret list`, `secret remove`)
 
+mod config;
 mod tool;
 
+pub use config::{ConfigCommand, run_config_command};
 pub use tool::{ToolCommand, run_tool_command};
 
 use clap::{Parser, Subcommand};
@@ -63,12 +65,13 @@ pub enum Command {
         channels_only: bool,
     },
 
+    /// Manage configuration settings
+    #[command(subcommand)]
+    Config(ConfigCommand),
+
     /// Manage WASM tools
     #[command(subcommand)]
     Tool(ToolCommand),
-    // Future: Secret management
-    // #[command(subcommand)]
-    // Secret(SecretCommand),
 }
 
 impl Cli {