fix(engine): auto-approve http calls with registered credentials in v2

The v1 approval flow (interactive yes/no prompt) doesn't exist in v2.
When the http tool returned UnlessAutoApproved for credentialed hosts,
the effect adapter blocked with LeaseDenied — making all skill-based
API calls fail.

Fix: credential-backed http calls bypass the v1 approval check. The
user authorized by storing the credential; the v1 interactive prompt
is redundant in v2's lease-based security model.

Co-Authored-By: Claude Opus 4.6 (1M context) <[email protected]>

src/tools/builtin/http.rs

@@ -366,7 +366,8 @@ fn parse_save_to_param(save_to: Option<&serde_json::Value>) -> Result<Option<Str
 }
 
 /// Extract host from URL in params (for approval checks).
-fn extract_host_from_params(params: &serde_json::Value) -> Option<String> {
+/// Extract the host from an HTTP tool's params (for credential registry lookup).
+pub fn extract_host_from_params(params: &serde_json::Value) -> Option<String> {
     params
         .get("url")
         .and_then(|u| u.as_str())

src/tools/builtin/mod.rs

@@ -23,7 +23,7 @@ pub use extension_tools::{
     ToolRemoveTool, ToolSearchTool, ToolUpgradeTool,
 };
 pub use file::{ApplyPatchTool, ListDirTool, ReadFileTool, WriteFileTool};
-pub use http::HttpTool;
+pub use http::{HttpTool, extract_host_from_params};
 pub use job::{
     CancelJobTool, CreateJobTool, JobEventsTool, JobPromptTool, JobStatusTool, ListJobsTool,
     PromptQueue, SchedulerSlot,