Add "Run" prefix for unnamed action steps (#36624)

Steps defined with `run:` or `uses:` without an explicit `name:` now
display with a "Run <cmd>" prefix in the Actions log UI, matching GitHub
Actions behavior.

<img width="311" height="236" alt="image"
src="https://github.com/user-attachments/assets/9fde83f5-c43a-4732-ac55-0f4e1fbc1314"
/>

---------

Signed-off-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

models/actions/task_test.go

@@ -0,0 +1,76 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package actions
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/nektos/act/pkg/jobparser"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMakeTaskStepDisplayName(t *testing.T) {
+	tests := []struct {
+		name     string
+		jobStep  *jobparser.Step
+		expected string
+	}{
+		{
+			name: "explicit name",
+			jobStep: &jobparser.Step{
+				Name: "Test Step",
+			},
+			expected: "Test Step",
+		},
+		{
+			name: "uses step",
+			jobStep: &jobparser.Step{
+				Uses: "actions/checkout@v4",
+			},
+			expected: "Run actions/checkout@v4",
+		},
+		{
+			name: "single-line run",
+			jobStep: &jobparser.Step{
+				Run: "echo hello",
+			},
+			expected: "Run echo hello",
+		},
+		{
+			name: "multi-line run block scalar",
+			jobStep: &jobparser.Step{
+				Run: "\n  echo hello  \r\n  echo world  \n  ",
+			},
+			expected: "Run echo hello",
+		},
+		{
+			name: "fallback to id",
+			jobStep: &jobparser.Step{
+				ID: "step-id",
+			},
+			expected: "Run step-id",
+		},
+		{
+			name: "very long name truncated",
+			jobStep: &jobparser.Step{
+				Name: strings.Repeat("a", 300),
+			},
+			expected: strings.Repeat("a", 252) + "…",
+		},
+		{
+			name: "very long run truncated",
+			jobStep: &jobparser.Step{
+				Run: strings.Repeat("a", 300),
+			},
+			expected: "Run " + strings.Repeat("a", 248) + "…",
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := makeTaskStepDisplayName(tt.jobStep, 255)
+			assert.Equal(t, tt.expected, result)
+		})
+	}
+}