fix(security): remediate unassigned CodeQL findings

- harden URL/request handling for composio and whatsapp integrations
- reduce cleartext logging exposure across providers/tools/gateway
- hash and constant-time compare gateway webhook secrets
- expand nested secret encryption coverage in config
- align feature aliases and add regression tests for security paths
- fix bubblewrap all-features test invocation surfaced during deep validation

src/tools/delegate.rs

@@ -16,8 +16,8 @@ const DELEGATE_TIMEOUT_SECS: u64 = 120;
 /// summarization) to purpose-built sub-agents.
 pub struct DelegateTool {
     agents: Arc<HashMap<String, DelegateAgentConfig>>,
-    /// Global API key fallback (from config.api_key)
-    fallback_api_key: Option<String>,
+    /// Global credential fallback (from config.api_key)
+    fallback_credential: Option<String>,
     /// Depth at which this tool instance lives in the delegation chain.
     depth: u32,
 }
@@ -25,11 +25,11 @@ pub struct DelegateTool {
 impl DelegateTool {
     pub fn new(
         agents: HashMap<String, DelegateAgentConfig>,
-        fallback_api_key: Option<String>,
+        fallback_credential: Option<String>,
     ) -> Self {
         Self {
             agents: Arc::new(agents),
-            fallback_api_key,
+            fallback_credential,
             depth: 0,
         }
     }
@@ -39,12 +39,12 @@ impl DelegateTool {
     /// their DelegateTool via this method with `depth: parent.depth + 1`.
     pub fn with_depth(
         agents: HashMap<String, DelegateAgentConfig>,
-        fallback_api_key: Option<String>,
+        fallback_credential: Option<String>,
         depth: u32,
     ) -> Self {
         Self {
             agents: Arc::new(agents),
-            fallback_api_key,
+            fallback_credential,
             depth,
         }
     }
@@ -165,13 +165,13 @@ impl Tool for DelegateTool {
         }
 
         // Create provider for this agent
-        let api_key = agent_config
+        let provider_credential = agent_config
             .api_key
             .as_deref()
-            .or(self.fallback_api_key.as_deref());
+            .or(self.fallback_credential.as_deref());
 
         let provider: Box<dyn Provider> =
-            match providers::create_provider(&agent_config.provider, api_key) {
+            match providers::create_provider(&agent_config.provider, provider_credential) {
                 Ok(p) => p,
                 Err(e) => {
                     return Ok(ToolResult {
@@ -268,7 +268,7 @@ mod tests {
                 provider: "openrouter".to_string(),
                 model: "anthropic/claude-sonnet-4-20250514".to_string(),
                 system_prompt: None,
-                api_key: Some("sk-test".to_string()),
+                api_key: Some("delegate-test-credential".to_string()),
                 temperature: None,
                 max_depth: 2,
             },