Support changing labels of Actions runner without re-registration (#24806)

close #24540

related:
- Protocol: https://gitea.com/gitea/actions-proto-def/pulls/9
- Runner side: https://gitea.com/gitea/act_runner/pulls/201

changes:
- Add column of `labels` to table `action_runner`, and combine the value
of `agent_labels` and `custom_labels` column to `labels` column.
- Store `labels` when registering `act_runner`.
- Update `labels` when `act_runner` starting and calling `Declare`.
- Users cannot modify the `custom labels` in edit page any more.

other changes:
- Store `version` when registering `act_runner`.
- If runner is latest version, parse version from `Declare`. But older
version runner still parse version from request header.

routers/web/shared/actions/runners.go

@@ -6,7 +6,6 @@ package actions
 import (
 	"errors"
 	"net/http"
-	"strings"
 
 	actions_model "code.gitea.io/gitea/models/actions"
 	"code.gitea.io/gitea/models/db"
@@ -126,9 +125,8 @@ func RunnerDetailsEditPost(ctx *context.Context, runnerID, ownerID, repoID int64
 
 	form := web.GetForm(ctx).(*forms.EditRunnerForm)
 	runner.Description = form.Description
-	runner.CustomLabels = splitLabels(form.CustomLabels)
 
-	err = actions_model.UpdateRunner(ctx, runner, "description", "custom_labels")
+	err = actions_model.UpdateRunner(ctx, runner, "description")
 	if err != nil {
 		log.Warn("RunnerDetailsEditPost.UpdateRunner failed: %v, url: %s", err, ctx.Req.URL)
 		ctx.Flash.Warning(ctx.Tr("actions.runners.update_runner_failed"))
@@ -176,11 +174,3 @@ func RunnerDeletePost(ctx *context.Context, runnerID int64,
 		"redirect": successRedirectTo,
 	})
 }
-
-func splitLabels(s string) []string {
-	labels := strings.Split(s, ",")
-	for i, v := range labels {
-		labels[i] = strings.TrimSpace(v)
-	}
-	return labels
-}