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/migrations/migrations.go

@@ -401,6 +401,7 @@ func prepareMigrationTasks() []*migration {
 		newMigration(324, "Fix closed milestone completeness for milestones with no issues", v1_26.FixClosedMilestoneCompleteness),
 		newMigration(325, "Fix missed repo_id when migrate attachments", v1_26.FixMissedRepoIDWhenMigrateAttachments),
 		newMigration(326, "Migrate commit status target URL to use run ID and job ID", v1_26.FixCommitStatusTargetURLToUseRunAndJobID),
+		newMigration(327, "Add disabled state to action runners", v1_26.AddDisabledToActionRunner),
 	}
 	return preparedMigrations
 }

models/migrations/v1_26/v327.go

@@ -0,0 +1,17 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package v1_26
+
+import "xorm.io/xorm"
+
+func AddDisabledToActionRunner(x *xorm.Engine) error {
+	type ActionRunner struct {
+		IsDisabled bool `xorm:"is_disabled NOT NULL DEFAULT false"`
+	}
+
+	_, err := x.SyncWithOptions(xorm.SyncOptions{
+		IgnoreDropIndices: true,
+	}, new(ActionRunner))
+	return err
+}

models/migrations/v1_26/v327_test.go

@@ -0,0 +1,33 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package v1_26
+
+import (
+	"testing"
+
+	"code.gitea.io/gitea/models/migrations/base"
+
+	"github.com/stretchr/testify/require"
+)
+
+func Test_AddDisabledToActionRunner(t *testing.T) {
+	type ActionRunner struct {
+		ID   int64 `xorm:"pk autoincr"`
+		Name string
+	}
+
+	x, deferable := base.PrepareTestEnv(t, 0, new(ActionRunner))
+	defer deferable()
+
+	_, err := x.Insert(&ActionRunner{Name: "runner"})
+	require.NoError(t, err)
+
+	require.NoError(t, AddDisabledToActionRunner(x))
+
+	var isDisabled bool
+	has, err := x.SQL("SELECT is_disabled FROM action_runner WHERE id = ?", 1).Get(&isDisabled)
+	require.NoError(t, err)
+	require.True(t, has)
+	require.False(t, isDisabled)
+}