feat: restructure plugin system, add Lua plugin support, update docs

internal/plugin/lua_plugin_test.go

@@ -0,0 +1,116 @@
+package plugin
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func TestTryLoadLua_Basic(t *testing.T) {
+	dir := t.TempDir()
+
+	os.WriteFile(filepath.Join(dir, "plugin.json"), []byte(`{
+		"name": "testlua",
+		"name_zh": "测试Lua",
+		"name_en": "Test Lua",
+		"version": "1.0.0",
+		"entry": "main.lua"
+	}`), 0644)
+
+	os.WriteFile(filepath.Join(dir, "main.lua"), []byte(`
+local plugin = {
+  name = "testlua"
+}
+
+function plugin.start(sdk)
+  sdk.log("info", "testlua started")
+  sdk.register_tool("testlua_hello", {
+    description = "Hello tool",
+    parameters = {type = "object", properties = {}}
+  }, function(args)
+    return {content = "hello from lua"}
+  end)
+end
+
+function plugin.stop()
+  sdk.log("info", "testlua stopped")
+end
+
+return plugin
+`), 0644)
+
+	plg, err := tryLoadLua(dir, "testlua", nil)
+	if err != nil {
+		t.Fatalf("tryLoadLua failed: %v", err)
+	}
+	if plg == nil {
+		t.Fatal("tryLoadLua returned nil")
+	}
+	if plg.Name() != "testlua" {
+		t.Fatalf("unexpected name: %s", plg.Name())
+	}
+	t.Logf("plugin loaded: %s", plg.Name())
+}
+
+func TestTryLoadLua_NoFile(t *testing.T) {
+	dir := t.TempDir()
+	plg, err := tryLoadLua(dir, "nonexistent", nil)
+	if err != nil {
+		t.Fatalf("tryLoadLua on empty dir should not error: %v", err)
+	}
+	if plg != nil {
+		t.Fatal("expected nil for non-existent main.lua")
+	}
+}
+
+func TestTryLoadLua_NoReturnTable(t *testing.T) {
+	dir := t.TempDir()
+
+	os.WriteFile(filepath.Join(dir, "plugin.json"), []byte(`{"name":"bad","entry":"main.lua"}`), 0644)
+	os.WriteFile(filepath.Join(dir, "main.lua"), []byte(`
+-- just code, no return table
+local x = 1
+sdk.log("info", "no return table test")
+`), 0644)
+
+	plg, err := tryLoadLua(dir, "bad", nil)
+	if err != nil {
+		t.Fatalf("tryLoadLua failed: %v", err)
+	}
+	if plg == nil {
+		t.Fatal("tryLoadLua returned nil")
+	}
+	t.Logf("loaded plugin without return table: %s", plg.Name())
+}
+
+func TestTryLoadLua_GlobalSDK(t *testing.T) {
+	dir := t.TempDir()
+
+	os.WriteFile(filepath.Join(dir, "plugin.json"), []byte(`{"name":"globalsdk","entry":"main.lua"}`), 0644)
+	os.WriteFile(filepath.Join(dir, "main.lua"), []byte(`
+-- sdk is a global, should work without return table
+sdk.log("info", "sdk is available as global")
+sdk.register_tool("direct_tool", {
+  description = "registered directly in top-level code"
+}, function(args)
+  return {result = "ok"}
+end)
+`), 0644)
+
+	plg, err := tryLoadLua(dir, "globalsdk", nil)
+	if err != nil {
+		t.Fatalf("tryLoadLua failed: %v", err)
+	}
+	if plg == nil {
+		t.Fatal("tryLoadLua returned nil")
+	}
+
+	lp := plg.(*luaPlugin)
+	lp.mu.Lock()
+	toolCount := len(lp.tools)
+	lp.mu.Unlock()
+	if toolCount != 1 {
+		t.Fatalf("expected 1 tool registration, got %d", toolCount)
+	}
+	t.Logf("tool registered during load phase: OK")
+}