Adds logical deletes to shared channel remotes and remote clusters (#28159)

* Adds logical deletes to shared channel remotes and remote clusters

Instead of physically deleting the shared channel remote and remote
clusters records when a channel is unshared, a remote uninvited or a
remote cluster is deleted, now those have a logical `DeleteAt` field
that is set.

This allows us to safely restore shared channels between two remote
clusters (as of now resetting the cursor without backfilling their
contents) and to know which connections were established in the past
and now are severed.

* Delete the index in remoteclusters before adding the new column

* Fix bad error check

server/public/model/client4.go

@@ -8781,6 +8781,9 @@ func (c *Client4) GetRemoteClusters(ctx context.Context, page, perPage int, filt
 	if filter.ExcludePlugins {
 		v.Set("exclude_plugins", "true")
 	}
+	if filter.IncludeDeleted {
+		v.Set("include_deleted", "true")
+	}
 	url := c.remoteClusterRoute()
 	if len(v) > 0 {
 		url += "?" + v.Encode()
@@ -8894,7 +8897,7 @@ func (c *Client4) DeleteRemoteCluster(ctx context.Context, remoteClusterId strin
 	return BuildResponse(r), nil
 }
 
-func (c *Client4) GetSharedChannelRemotesByRemoteCluster(ctx context.Context, remoteId string, excludeHome, excludeRemote bool, page, perPage int) ([]*SharedChannelRemote, *Response, error) {
+func (c *Client4) GetSharedChannelRemotesByRemoteCluster(ctx context.Context, remoteId string, excludeHome, excludeRemote, includeDeleted bool, page, perPage int) ([]*SharedChannelRemote, *Response, error) {
 	v := url.Values{}
 	if excludeHome {
 		v.Set("exclude_home", "true")
@@ -8902,6 +8905,9 @@ func (c *Client4) GetSharedChannelRemotesByRemoteCluster(ctx context.Context, re
 	if excludeRemote {
 		v.Set("exclude_remote", "true")
 	}
+	if includeDeleted {
+		v.Set("include_deleted", "true")
+	}
 	if page != 0 {
 		v.Set("page", fmt.Sprintf("%d", page))
 	}

server/public/model/remote_cluster.go

@@ -57,6 +57,7 @@ type RemoteCluster struct {
 	SiteURL       string  `json:"site_url"`
 	DefaultTeamId string  `json:"default_team_id"`
 	CreateAt      int64   `json:"create_at"`
+	DeleteAt      int64   `json:"delete_at"`
 	LastPingAt    int64   `json:"last_ping_at"`
 	Token         string  `json:"token"`
 	RemoteToken   string  `json:"remote_token"`
@@ -75,6 +76,7 @@ func (rc *RemoteCluster) Auditable() map[string]interface{} {
 		"site_url":        rc.SiteURL,
 		"default_team_id": rc.DefaultTeamId,
 		"create_at":       rc.CreateAt,
+		"delete_at":       rc.DeleteAt,
 		"last_ping_at":    rc.LastPingAt,
 		"creator_id":      rc.CreatorId,
 		"plugin_id":       rc.PluginID,
@@ -271,6 +273,7 @@ func (rc *RemoteCluster) ToRemoteClusterInfo() RemoteClusterInfo {
 		Name:        rc.Name,
 		DisplayName: rc.DisplayName,
 		CreateAt:    rc.CreateAt,
+		DeleteAt:    rc.DeleteAt,
 		LastPingAt:  rc.LastPingAt,
 	}
 }
@@ -284,6 +287,7 @@ type RemoteClusterInfo struct {
 	Name        string `json:"name"`
 	DisplayName string `json:"display_name"`
 	CreateAt    int64  `json:"create_at"`
+	DeleteAt    int64  `json:"delete_at"`
 	LastPingAt  int64  `json:"last_ping_at"`
 }
 
@@ -457,4 +461,5 @@ type RemoteClusterQueryFilter struct {
 	OnlyPlugins    bool
 	ExcludePlugins bool
 	RequireOptions Bitmask
+	IncludeDeleted bool
 }

server/public/model/shared_channel.go

@@ -110,6 +110,7 @@ type SharedChannelRemote struct {
 	CreatorId         string `json:"creator_id"`
 	CreateAt          int64  `json:"create_at"`
 	UpdateAt          int64  `json:"update_at"`
+	DeleteAt          int64  `json:"delete_at"`
 	IsInviteAccepted  bool   `json:"is_invite_accepted"`
 	IsInviteConfirmed bool   `json:"is_invite_confirmed"`
 	RemoteId          string `json:"remote_id"`
@@ -265,6 +266,7 @@ type SharedChannelRemoteFilterOpts struct {
 	InclUnconfirmed bool
 	ExcludeHome     bool
 	ExcludeRemote   bool
+	IncludeDeleted  bool
 }
 
 // SyncMsg represents a change in content (post add/edit/delete, reaction add/remove, users).