Fix TestScripts failures - add bd binary to PATH

TestScripts was failing with 'exit status 127' because test scripts use
'exec sh -c bd ...' which spawns a shell subprocess that doesn't have
access to the script engine's registered bd command.

Solution: Add the temp directory containing the built bd binary to the
PATH environment variable when running tests, so shell subprocesses can
find the bd executable.

This fixes the last remaining CI failures.

Amp-Thread-ID: https://ampcode.com/threads/T-63ef3a7d-8efe-472d-97ed-6ac95bd8318b
Co-authored-by: Amp <amp@ampcode.com>

cmd/bd/scripttest_test.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"context"
+	"os"
 	"os/exec"
 	"path/filepath"
 	"runtime"
@@ -20,7 +21,8 @@ func TestScripts(t *testing.T) {
 
 	// Build the bd binary
 	exeName := "bd"
-	exe := filepath.Join(t.TempDir(), exeName)
+	binDir := t.TempDir()
+	exe := filepath.Join(binDir, exeName)
 	if err := exec.Command("go", "build", "-o", exe, ".").Run(); err != nil {
 		t.Fatal(err)
 	}
@@ -29,7 +31,11 @@ func TestScripts(t *testing.T) {
 	timeout := 2 * time.Second
 	engine := script.NewEngine()
 	engine.Cmds["bd"] = script.Program(exe, nil, timeout)
-
+	
+	// Add binDir to PATH so 'sh -c bd ...' works in test scripts
+	currentPath := os.Getenv("PATH")
+	env := []string{"PATH=" + binDir + ":" + currentPath}
+	
 	// Run all tests
-	scripttest.Test(t, context.Background(), engine, nil, "testdata/*.txt")
+	scripttest.Test(t, context.Background(), engine, env, "testdata/*.txt")
 }