Feature: Add per-runner “Disable/Pause” (#36776)

This PR adds per-runner disable/enable support for Gitea Actions so a
registered runner can be paused from picking up new jobs without
unregistering.

Disabled runners stay registered and online but are excluded from new
task assignment; running tasks are allowed to finish. Re-enabling
restores pickup, and runner list/get responses now expose disabled
state.

Also added an endpoint for testing
http://localhost:3000/devtest/runner-edit/enable

<img width="1509" height="701" alt="Bildschirmfoto 2026-02-27 um 22 13
24"
src="https://github.com/user-attachments/assets/5328eda9-e59c-46b6-b398-f436e50ee3da"
/>


Fixes: https://github.com/go-gitea/gitea/issues/36767

models/actions/runner.go

@@ -62,6 +62,8 @@ type ActionRunner struct {
 	AgentLabels []string `xorm:"TEXT"`
 	// Store if this is a runner that only ever get one single job assigned
 	Ephemeral bool `xorm:"ephemeral NOT NULL DEFAULT false"`
+	// Store if this runner is disabled and should not pick up new jobs
+	IsDisabled bool `xorm:"is_disabled NOT NULL DEFAULT false"`
 
 	Created timeutil.TimeStamp `xorm:"created"`
 	Updated timeutil.TimeStamp `xorm:"updated"`
@@ -199,6 +201,7 @@ type FindRunnerOptions struct {
 	Sort          string
 	Filter        string
 	IsOnline      optional.Option[bool]
+	IsDisabled    optional.Option[bool]
 	WithAvailable bool // not only runners belong to, but also runners can be used
 }
 
@@ -239,6 +242,10 @@ func (opts FindRunnerOptions) ToConds() builder.Cond {
 			cond = cond.And(builder.Lte{"last_online": time.Now().Add(-RunnerOfflineTime).Unix()})
 		}
 	}
+
+	if opts.IsDisabled.Has() {
+		cond = cond.And(builder.Eq{"is_disabled": opts.IsDisabled.Value()})
+	}
 	return cond
 }
 
@@ -297,6 +304,20 @@ func UpdateRunner(ctx context.Context, r *ActionRunner, cols ...string) error {
 	return err
 }
 
+func SetRunnerDisabled(ctx context.Context, runner *ActionRunner, isDisabled bool) error {
+	if runner.IsDisabled == isDisabled {
+		return nil
+	}
+
+	return db.WithTx(ctx, func(ctx context.Context) error {
+		runner.IsDisabled = isDisabled
+		if err := UpdateRunner(ctx, runner, "is_disabled"); err != nil {
+			return err
+		}
+		return IncreaseTaskVersion(ctx, runner.OwnerID, runner.RepoID)
+	})
+}
+
 // DeleteRunner deletes a runner by given ID.
 func DeleteRunner(ctx context.Context, id int64) error {
 	if _, err := GetRunnerByID(ctx, id); err != nil {