feat: remove console statements from SDK code

- Remove all console.log, console.warn, and console.error from src/client and src/server
- Add ESLint no-console rule for client and server directories (excluding tests)
- Keep console statements in test files, examples, and CLI tools as intended

Addresses feedback in PR #665

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

eslint.config.mjs

@@ -15,5 +15,12 @@ export default tseslint.config(
                 { "argsIgnorePattern": "^_" }
             ]
         }
+    },
+    {
+        files: ["src/client/**/*.ts", "src/server/**/*.ts"],
+        ignores: ["**/*.test.ts"],
+        rules: {
+            "no-console": "error"
+        }
     }
 );