feat(actions): Add Actions API endpoints for workflow run management and logs (#35382)

Implements the missing REST API endpoints for Actions workflow run
management:

1. `POST /actions/runs/{run}/cancel` cancels a run and its jobs, `409`
when it already finished
1. `POST /actions/runs/{run}/approve` approves a run awaiting approval,
idempotent, `409` when it never awaited one
1. `GET /actions/runs/{run}/logs` downloads the latest attempt's job
logs as a zip archive

`ActionWorkflowRun` gains `created_at`, `updated_at` and the `jobs_url`,
`logs_url`, `artifacts_url`, `cancel_url` and `rerun_url` fields, and
now always emits `conclusion` and `head_branch`.

Cancellation is shared with the web handler in `services/actions`.

Fixes https://github.com/go-gitea/gitea/issues/35176
Fixes https://github.com/go-gitea/gitea/issues/36554

---------

Co-authored-by: Claude Sonnet 4.6 <claude-sonnet-4-6@anthropic.com>
Co-authored-by: OpenCode Agent <opencode@rossgolder.com>
Co-authored-by: Nicolas <bircni@icloud.com>
Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

modules/structs/repo_actions.go

@@ -111,6 +111,11 @@ type ActionWorkflowRun struct {
 	// It is set only when the current attempt is > 1 (i.e. a rerun). For the first attempt, or for legacy runs that pre-date ActionRunAttempt, it is null.
 	PreviousAttemptURL *string `json:"previous_attempt_url"`
 	HTMLURL            string  `json:"html_url"`
+	JobsURL            string  `json:"jobs_url"`
+	LogsURL            string  `json:"logs_url"`
+	ArtifactsURL       string  `json:"artifacts_url"`
+	CancelURL          string  `json:"cancel_url"`
+	RerunURL           string  `json:"rerun_url"`
 	DisplayTitle       string  `json:"display_title"`
 	Path               string  `json:"path"`
 	Event              string  `json:"event"`
@@ -130,6 +135,10 @@ type ActionWorkflowRun struct {
 	Conclusion     string                `json:"conclusion,omitempty"`
 	PullRequests   []*PullRequestMinimal `json:"pull_requests"`
 	// swagger:strfmt date-time
+	CreatedAt time.Time `json:"created_at"`
+	// swagger:strfmt date-time
+	UpdatedAt time.Time `json:"updated_at"`
+	// swagger:strfmt date-time
 	StartedAt time.Time `json:"started_at"`
 	// swagger:strfmt date-time
 	CompletedAt time.Time `json:"completed_at"`