Fix: remove duplicated/broken pool-opening blocks in skald-setup main

A botched edit left three overlapping fragments in `run()`, one
referencing an undefined `exe_dir`. Only the last was syntactically
balanced, so the file did not compile. Collapse to a single cwd-relative
`init_system_pool(SYSTEM_DB_PATH)` block, consistent with the rest of
the project.

crates/skald-setup/src/main.rs

@@ -89,18 +89,6 @@ fn usage() -> String {
 async fn run(mode: Mode) -> Result<std::process::ExitCode> {
     // Opening the pool creates `database/system.db` and its schema if absent —
     // the same call the server makes, so setup and server agree on the layout.
-    let pool = std::sync::Arc::new(
-        db::init_system_pool(SYSTEM_DB_PATH)
-            .await
-            .context("opening the system database")?,
-    let db_path = exe_dir.join(SYSTEM_DB_PATH);
-
-    // Opening the pool creates the database and its schema if absent — the same
-    // call the server makes, so setup and server agree on the layout.
-    let pool = std::sync::Arc::new(
-        db::init_system_pool(&db_path)
-            .await
-            .context("opening the system database")?,
     let pool = std::sync::Arc::new(
         db::init_system_pool(SYSTEM_DB_PATH)
             .await