refactor: add services layer on the Gitea Go SDK (#1125)

- `internal/services`: typed Gitea workflows built on `gitea.dev/sdk`, independent of CLI flags and terminal I/O: issues, pull requests, reviews, comments, labels, milestones, releases and assets, repositories, branches, wiki, Actions (workflows, runs, jobs, logs, artifacts, secrets, variables), organizations, teams, webhooks, notifications, SSH keys, tracked time, admin users, search and status.
- SDK types are mapped to tea's own output types, so `--json` stays a stable contract. Requests the SDK cannot express yet (e.g. pull list filters, multi-status run lists, org label archiving) go through small raw helpers, each marked `TODO(sdk)` with the missing SDK piece.
- Targets Gitea 28 or newer: no version or API-schema probing. List helpers fill pages capped by `MAX_RESPONSE_ITEMS`.

Nothing imports this package yet.

Reviewed-on: https://gitea.com/gitea/tea/pulls/1125
Reviewed-by: TheFox0x7 <95654+thefox0x7@noreply.gitea.com>

internal/services/repository_setup.go

@@ -0,0 +1,97 @@
+// Copyright 2026 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package services
+
+import (
+	"context"
+	"errors"
+	"net/http"
+	"time"
+
+	gitea "gitea.dev/sdk"
+	"gitea.dev/tea/internal/transport"
+)
+
+// RepositoryTemplateOptions controls copying from a template repository.
+type RepositoryTemplateOptions struct {
+	Name          string `json:"name"`
+	Owner         string `json:"owner"`
+	Description   string `json:"description"`
+	DefaultBranch string `json:"default_branch,omitempty"`
+	Private       bool   `json:"private"`
+	Content       bool   `json:"git_content"`
+	GitHooks      bool   `json:"git_hooks"`
+	Avatar        bool   `json:"avatar"`
+	Labels        bool   `json:"labels"`
+	Topics        bool   `json:"topics"`
+	Webhooks      bool   `json:"webhooks"`
+}
+
+// Generate creates a repository from a template on the selected instance.
+func (s Repositories) Generate(ctx context.Context, source string, opts RepositoryTemplateOptions) (Repository, error) {
+	if opts.Owner == "" {
+		account, err := CurrentAccount(ctx, s.Client)
+		if err != nil {
+			return Repository{}, err
+		}
+		opts.Owner = account
+	}
+	// TODO(sdk): CreateRepoFromTemplateOption has no default_branch.
+	var response gitea.Repository
+	if err := sendJSON(ctx, s.Client, http.MethodPost, "repos/"+source+"/generate", opts, &response); err != nil {
+		return Repository{}, err
+	}
+	return repositoryFrom(&response), nil
+}
+
+// RepositoryMigrationOptions is explicit server-side import input. Credentials stay in request bodies.
+type RepositoryMigrationOptions struct {
+	Name           string        `json:"repo_name"`
+	Owner          string        `json:"repo_owner,omitempty"`
+	CloneURL       string        `json:"clone_addr"`
+	Service        string        `json:"service"`
+	AuthUser       string        `json:"auth_username,omitempty"`
+	AuthPassword   string        `json:"auth_password,omitempty"`
+	AuthToken      string        `json:"auth_token,omitempty"`
+	Mirror         bool          `json:"mirror"`
+	Private        bool          `json:"private"`
+	Description    string        `json:"description,omitempty"`
+	Wiki           bool          `json:"wiki"`
+	Milestones     bool          `json:"milestones"`
+	Labels         bool          `json:"labels"`
+	Issues         bool          `json:"issues"`
+	PullRequests   bool          `json:"pull_requests"`
+	Releases       bool          `json:"releases"`
+	MirrorInterval string        `json:"mirror_interval,omitempty"`
+	LFS            bool          `json:"lfs"`
+	LFSEndpoint    string        `json:"lfs_endpoint,omitempty"`
+	Timeout        time.Duration `json:"-"`
+}
+
+// Migrate imports a remote repository through Gitea's migration API.
+func (s Repositories) Migrate(ctx context.Context, opts RepositoryMigrationOptions) (Repository, error) {
+	if opts.Timeout > 0 {
+		var cancel context.CancelFunc
+		ctx, cancel = context.WithTimeout(ctx, opts.Timeout)
+		defer cancel()
+		s.Client = s.Client.WithTimeout(opts.Timeout)
+	}
+	item, _, err := call(ctx, s.Client, func(ctx context.Context, c *gitea.Client) (*gitea.Repository, *gitea.Response, error) {
+		return c.Repositories.MigrateRepo(ctx, gitea.MigrateRepoOption{
+			RepoName: opts.Name, RepoOwner: opts.Owner, CloneAddr: opts.CloneURL, Service: gitea.GitServiceType(opts.Service),
+			AuthUsername: opts.AuthUser, AuthPassword: opts.AuthPassword, AuthToken: opts.AuthToken, Mirror: opts.Mirror,
+			Private: opts.Private, Description: opts.Description, Wiki: opts.Wiki, Milestones: opts.Milestones,
+			Labels: opts.Labels, Issues: opts.Issues, PullRequests: opts.PullRequests, Releases: opts.Releases,
+			MirrorInterval: opts.MirrorInterval, LFS: opts.LFS, LFSEndpoint: opts.LFSEndpoint,
+		})
+	})
+	if err != nil {
+		// The server may echo source credentials in its error message.
+		if failure, ok := errors.AsType[*transport.APIError](err); ok && (opts.AuthPassword != "" || opts.AuthToken != "") {
+			failure.Message = ""
+		}
+		return Repository{}, err
+	}
+	return repositoryFrom(item), nil
+}