[MM-31247] Add support for compressed export files with attachments (#16614)

* Include filepaths for post attachments

* Cleanup

* Enable exporting file attachments

* Fix file import

* Enable zip export

* Support creating missing directories when unzipping

* Add test

* Add translations

* Export direct channel posts attachments

* Fix returned values order

Remove pointer to slice in return

* [MM-31597] Implement export process job (#16626)

* Implement export process job

* Add translations

* Remove unused value

* [MM-31249] Add /exports API endpoint (#16633)

* Implement API endpoints to list, download and delete export files

* Add endpoint for single resource

* Update i18n/en.json

Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

* Update i18n/en.json

Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

* Fix var name

Co-authored-by: Ibrahim Serdar Acikgoz <serdaracikgoz86@gmail.com>

i18n/en.json

@@ -1324,6 +1324,10 @@
     "id": "api.emoji.upload.open.app_error",
     "translation": "Unable to create the emoji. An error occurred when trying to open the attached image."
   },
+  {
+    "id": "api.export.export_not_found.app_error",
+    "translation": "Unable to find export file."
+  },
   {
     "id": "api.file.append_file.app_error",
     "translation": "Unable to append data to the file."
@@ -4086,6 +4090,22 @@
     "id": "app.emoji.get_list.internal_error",
     "translation": "Unable to get the emoji."
   },
+  {
+    "id": "app.export.export_attachment.copy_file.error",
+    "translation": "Failed to copy file during export."
+  },
+  {
+    "id": "app.export.export_attachment.create_file.error",
+    "translation": "Failed to created file during export."
+  },
+  {
+    "id": "app.export.export_attachment.mkdirall.error",
+    "translation": "Failed to create directory during export."
+  },
+  {
+    "id": "app.export.export_attachment.zip_create_header.error",
+    "translation": "Failed to create zip header during export."
+  },
   {
     "id": "app.export.export_custom_emoji.copy_emoji_images.error",
     "translation": "Unable to copy custom emoji images"
@@ -4098,6 +4118,14 @@
     "id": "app.export.export_write_line.json_marshall.error",
     "translation": "An error occurred marshalling the JSON data for export."
   },
+  {
+    "id": "app.export.marshal.app_error",
+    "translation": "Unable to marshal response."
+  },
+  {
+    "id": "app.export.zip_create.error",
+    "translation": "Failed to add file to zip archive during export."
+  },
   {
     "id": "app.file_info.get.app_error",
     "translation": "Unable to get the file info."
@@ -4146,6 +4174,10 @@
     "id": "app.import.attachment.file_upload.error",
     "translation": "Error uploading the file: \"{{.FilePath}}\""
   },
+  {
+    "id": "app.import.attachment.read_file_data.error",
+    "translation": "Failed to read file attachment during import."
+  },
   {
     "id": "app.import.bulk_import.file_scan.error",
     "translation": "Error reading import data file."
@@ -7274,6 +7306,14 @@
     "id": "model.config.is_valid.encrypt_sql.app_error",
     "translation": "Invalid at rest encrypt key for SQL settings. Must be 32 chars or more."
   },
+  {
+    "id": "model.config.is_valid.export.directory.app_error",
+    "translation": "Value for Directory should not be empty."
+  },
+  {
+    "id": "model.config.is_valid.export.retention_days_too_low.app_error",
+    "translation": "Invalid value for RetentionDays. Value should be greater than 0"
+  },
   {
     "id": "model.config.is_valid.file_driver.app_error",
     "translation": "Invalid driver name for file settings. Must be 'local' or 'amazons3'."