feat: refactor trade API to return execution status with signature

- Bump version from 1.2.0 to 1.2.1
- Change trade methods return type from Signature to (bool, Signature)
- Improve parallel execution error handling and status tracking
- Update CLI examples to match new API interface
- Enhance transaction success/failure reporting capabilities

Breaking Change: Trade API now returns tuple (success_status, signature)

src/lib.rs

@@ -257,7 +257,7 @@ impl SolanaTrade {
     /// - Network or RPC errors occur
     /// - Insufficient SOL balance for the purchase
     /// - Required accounts cannot be created or accessed
-    pub async fn buy(&self, params: TradeBuyParams) -> Result<Signature, anyhow::Error> {
+    pub async fn buy(&self, params: TradeBuyParams) -> Result<(bool, Signature), anyhow::Error> {
         if params.slippage_basis_points.is_none() {
             println!(
                 "slippage_basis_points is none, use default slippage basis points: {}",
@@ -346,7 +346,7 @@ impl SolanaTrade {
     /// - Insufficient token balance for the sale
     /// - Token account doesn't exist or is not properly initialized
     /// - Required accounts cannot be created or accessed
-    pub async fn sell(&self, params: TradeSellParams) -> Result<Signature, anyhow::Error> {
+    pub async fn sell(&self, params: TradeSellParams) -> Result<(bool, Signature), anyhow::Error> {
         if params.slippage_basis_points.is_none() {
             println!(
                 "slippage_basis_points is none, use default slippage basis points: {}",
@@ -447,7 +447,7 @@ impl SolanaTrade {
         mut params: TradeSellParams,
         amount_token: u64,
         percent: u64,
-    ) -> Result<Signature, anyhow::Error> {
+    ) -> Result<(bool, Signature), anyhow::Error> {
         if percent == 0 || percent > 100 {
             return Err(anyhow::anyhow!("Percentage must be between 1 and 100"));
         }