[MM-64686] Expose audit logging functionality via plugin API (#31204)

This commit exposes audit logging functionality to plugins via the plugin API, allowing plugins to create and log audit records. Additionally, it addresses a gob encoding issue that could cause plugin crashes when audit data contains nil pointers or unregistered types.

server/channels/api4/post_local.go

@@ -6,8 +6,8 @@ package api4
 import (
 	"net/http"
 
+	"github.com/mattermost/mattermost/server/public/model"
 	"github.com/mattermost/mattermost/server/v8/channels/app"
-	"github.com/mattermost/mattermost/server/v8/channels/audit"
 )
 
 func (api *API) InitPostLocal() {
@@ -24,10 +24,10 @@ func localDeletePost(c *Context, w http.ResponseWriter, r *http.Request) {
 
 	permanent := c.Params.Permanent
 
-	auditRec := c.MakeAuditRecord("localDeletePost", audit.Fail)
+	auditRec := c.MakeAuditRecord("localDeletePost", model.AuditStatusFail)
 	defer c.LogAuditRecWithLevel(auditRec, app.LevelContent)
-	audit.AddEventParameter(auditRec, "post_id", c.Params.PostId)
-	audit.AddEventParameter(auditRec, "permanent", permanent)
+	model.AddEventParameterToAuditRec(auditRec, "post_id", c.Params.PostId)
+	model.AddEventParameterToAuditRec(auditRec, "permanent", permanent)
 
 	includeDeleted := permanent