fix(actions): correctness and hardening fixes (#38518)

Various fixes to actions

1. **Cap total jobs per run in reusable-workflow expansion** — only
nesting depth was capped, so fan-out + nested reusable workflows could
explode job-row inserts and exhaust the DB from a single push. Now
enforces `MaxJobNumPerRun` in the insert path.
2. **Reject rerun-failed when a run has no failed jobs** — an empty job
list meant "re-run everything", so `rerun-failed` on a green run re-ran
all jobs. Now errors (web + API).
3. **Don't adopt external commit statuses into the legacy hash** — the
pre-#35699 Context-only hash matched API-posted statuses too, collapsing
two same-named workflows into one check. Now limited to Actions-user
rows.
4. **Don't cut post-cancel cleanup short in `StopEndlessTasks`** — the
sweep force-stopped just-cancelled jobs mid-cleanup. Now targets
`StatusRunning` only; stalled cancels stay covered by `StopZombieTasks`.
5. **Avoid redundant run reload in `GenerateGiteaContext`** — resolving
`github.triggering_actor` reloaded the run already passed in. Now loads
only the trigger user via new `ActionRunAttempt.LoadTriggerUser`.

---------

Co-authored-by: Zettat123 <zettat123@gmail.com>
Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

services/actions/clear_tasks_test.go

@@ -4,11 +4,16 @@
 package actions
 
 import (
+	"fmt"
 	"testing"
+	"time"
 
 	actions_model "gitea.dev/models/actions"
 	"gitea.dev/models/db"
 	"gitea.dev/models/unittest"
+	"gitea.dev/modules/setting"
+	"gitea.dev/modules/test"
+	"gitea.dev/modules/timeutil"
 
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -88,3 +93,51 @@ func TestShouldBlockRunByConcurrency_CancellingJobBlocks(t *testing.T) {
 	require.NoError(t, err)
 	assert.True(t, shouldBlock)
 }
+
+// TestStopEndlessTasksSkipsCancelling verifies that a task running its post-cancel cleanup is not
+// force-stopped by the endless-task sweep just because the job started long ago.
+func TestStopEndlessTasksSkipsCancelling(t *testing.T) {
+	require.NoError(t, unittest.PrepareTestDatabase())
+
+	// StopEndlessTasks emits ready jobs onto the emitter queue, mock it
+	defer test.MockVariableValue(&EmitJobsIfReadyByRun, func(runID int64) error { return nil })()
+
+	// well past the endless-task threshold, keyed on the task's start time
+	longAgo := timeutil.TimeStamp(time.Now().Add(-2 * setting.Actions.EndlessTaskTimeout).Unix())
+
+	var seq int64
+	newTaskWithJob := func(status actions_model.Status) *actions_model.ActionTask {
+		seq++
+		run := &actions_model.ActionRun{
+			RepoID: 1, OwnerID: 2, TriggerUserID: 2, WorkflowID: "test.yml",
+			Index: 99500 + seq, Ref: "refs/heads/main", Status: actions_model.StatusRunning,
+		}
+		require.NoError(t, db.Insert(t.Context(), run))
+		attempt := &actions_model.ActionRunAttempt{
+			RepoID: run.RepoID, RunID: run.ID, Attempt: 1, TriggerUserID: run.TriggerUserID, Status: actions_model.StatusRunning,
+		}
+		require.NoError(t, db.Insert(t.Context(), attempt))
+		job := &actions_model.ActionRunJob{
+			RunID: run.ID, RunAttemptID: attempt.ID, AttemptJobID: 1, RepoID: run.RepoID, OwnerID: run.OwnerID,
+			CommitSHA: "c2d72f548424103f01ee1dc02889c1e2bff816b0", Name: "j", JobID: "j", Status: status,
+		}
+		require.NoError(t, db.Insert(t.Context(), job))
+		task := &actions_model.ActionTask{
+			JobID: job.ID, RepoID: run.RepoID, OwnerID: run.OwnerID,
+			CommitSHA: job.CommitSHA, Status: status, Started: longAgo,
+			TokenHash: fmt.Sprintf("endless-test-token-%d", seq), TokenSalt: "salt",
+		}
+		require.NoError(t, db.Insert(t.Context(), task))
+		return task
+	}
+
+	running := newTaskWithJob(actions_model.StatusRunning)
+	cancelling := newTaskWithJob(actions_model.StatusCancelling)
+
+	require.NoError(t, StopEndlessTasks(t.Context()))
+
+	runningAfter := unittest.AssertExistsAndLoadBean(t, &actions_model.ActionTask{ID: running.ID})
+	cancellingAfter := unittest.AssertExistsAndLoadBean(t, &actions_model.ActionTask{ID: cancelling.ID})
+	assert.Equal(t, actions_model.StatusFailure, runningAfter.Status, "long-running task should be force-stopped")
+	assert.Equal(t, actions_model.StatusCancelling, cancellingAfter.Status, "cancelling task should keep running its cleanup")
+}