refactor: simplify CLI commands and update architecture docs

1. Simplify CLI:
   - Make 'onboard' quick setup default (remove --quick)
   - Add --interactive flag for full wizard
   - Make 'status' detailed by default (remove --verbose)
   - Remove 'tools list/test' and 'integrations list' commands
   - Add 'channel doctor' command
2. Update Docs:
   - Update architecture.svg with Channel allowlists, Browser allowlist, and latest stats
   - Update README.md with new command usage and browser/channel config details
3. Polish:
   - Browser tool integration
   - Channel allowlist logic (empty = deny all)

src/providers/mod.rs

@@ -104,7 +104,7 @@ pub fn create_provider(name: &str, api_key: Option<&str>) -> anyhow::Result<Box<
         }
 
         _ => anyhow::bail!(
-            "Unknown provider: {name}. Run `zeroclaw integrations list -c ai` to see all available providers.\n\
+            "Unknown provider: {name}. Check README for supported providers or run `zeroclaw onboard --interactive` to reconfigure.\n\
              Tip: Use \"custom:https://your-api.com\" for any OpenAI-compatible endpoint."
         ),
     }