feat: add deploy tokens (#37306)

Deploy keys only work over SSH. A deploy token is their counterpart for HTTPS: a repository scoped credential, used as the password of a Git request, with read or read and write access. It covers Git operations and LFS, and can be regenerated in place.

Signed-off-by: silverwind <me@silverwind.io>
Co-authored-by: Claude Mythos <noreply@anthropic.com>
Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: bircni <bircni@icloud.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

modelmigration/v28/v352.go

@@ -0,0 +1,38 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package v28
+
+import (
+	"context"
+
+	"gitea.dev/modelmigration/base"
+
+	"xorm.io/xorm"
+)
+
+func AddTokenToDeployKey(ctx context.Context, x base.EngineMigration) error {
+	// Drop the old UNIQUE(s) index on (key_id, repo_id). Every token row carries key
+	// id 0, so the pair can no longer be unique. AddDeployKey still checks it in code.
+	indexes, err := x.Dialect().GetIndexes(x.DB(), ctx, "deploy_key")
+	if err != nil {
+		return err
+	}
+	if idx, ok := indexes["s"]; ok {
+		if _, err := x.Exec(x.Dialect().DropIndexSQL("deploy_key", idx)); err != nil {
+			return err
+		}
+	}
+
+	type DeployKey struct {
+		KeyID     int64  `xorm:"INDEX"`
+		RepoID    int64  `xorm:"INDEX"`
+		KeyType   int    `xorm:"NOT NULL DEFAULT 1"` // every existing row is an SSH key
+		TokenHash string `xorm:"INDEX"`
+	}
+	_, err = x.SyncWithOptions(xorm.SyncOptions{
+		IgnoreConstrains:  true,
+		IgnoreDropIndices: true, // the bean only describes the new columns
+	}, new(DeployKey))
+	return err
+}