fix(docs): enhance PQL manifest documentation for clarity and detail

docs-website/router/configuration.mdx

@@ -1175,7 +1175,8 @@ These rules apply to requests being made from the Router to all Subgraphs.
 | PERSISTED_OPERATIONS_STORAGE_OBJECT_PREFIX | persisted_operations.storage.object_prefix | <Icon icon="square" />                        | The prefix of the object in the storage provider location. The prefix is put in front of the operation SHA256 hash. \$prefix/SHA256.json                                                               |               |
 | PERSISTED_OPERATIONS_LOG_UNKNOWN           | persisted_operations.log_unknown           | <Icon icon="square" />                        | Log operations (sent with the operation body) which haven't yet been persisted. If the value is true, all operations not yet persisted are logged to the router logs.                                  | false         |
 | PERSISTED_OPERATIONS_SAFELIST_ENABLED      | persisted_operations.safelist.enabled      | <Icon icon="square" />                        | Only allows persisted operations (sent with operation body). If the value is true, all operations not explicitly added to the safelist are blocked.                                                    | false         |
-| PERSISTED_OPERATIONS_MANIFEST_ENABLED      | persisted_operations.manifest.enabled      | <Icon icon="square" />                        | Enable the PQL manifest. When enabled, the router loads all persisted operations from a single `manifest.json` file and serves them from memory. Uses the `storage` config above when a provider is set, otherwise fetches from the Cosmo CDN. Only S3 and CDN storage providers are supported. | false         |
+| PERSISTED_OPERATIONS_MANIFEST_ENABLED      | persisted_operations.manifest.enabled      | <Icon icon="square" />                        | Enable the PQL manifest. When enabled, the router loads all persisted operations from a single manifest file and serves them from memory. Uses the `storage` config above when a provider is set, otherwise fetches from the Cosmo CDN. Only S3 and CDN storage providers are supported. | false         |
+| PERSISTED_OPERATIONS_MANIFEST_FILE_NAME    | persisted_operations.manifest.file_name    | <Icon icon="square" />                        | The manifest file name. Only used when a custom storage provider is configured. The router resolves the full object path as `<object_prefix>/<file_name>`. Use a `.gz` or `.zst` extension (e.g. `manifest.json.gz`) to enable transparent decompression. Ignored in CDN mode. | manifest.json |
 | PERSISTED_OPERATIONS_MANIFEST_POLL_INTERVAL| persisted_operations.manifest.poll_interval| <Icon icon="square" />                        | The interval at which the router polls the Cosmo CDN for manifest updates (only when no storage provider is configured). Minimum 10s.                                                                 | 10s           |
 | PERSISTED_OPERATIONS_MANIFEST_POLL_JITTER  | persisted_operations.manifest.poll_jitter  | <Icon icon="square" />                        | Random jitter added to each poll interval to avoid thundering herd. Minimum 1s.                                                                                                                        | 5s            |
 

docs-website/router/persisted-queries/persisted-operations.mdx

@@ -118,7 +118,7 @@ Operations are currently deleted one at a time from the UI.
 
 ## PQL Manifest
 
-By default, the router fetches persisted operations individually from the Cosmo CDN on each request. When the **PQL manifest** is enabled, the router instead loads all persisted operations from a single `manifest.json` file at startup and serves them entirely from memory — eliminating per-request network overhead.
+By default, the router fetches persisted operations individually from the Cosmo CDN on each request. When the **PQL manifest** is enabled, the router instead loads all persisted operations from a single manifest file at startup and serves them entirely from memory, eliminating per-request network overhead.
 
 ```yaml
 persisted_operations:

router/pkg/config/config.schema.json

@@ -206,7 +206,7 @@
             "file_name": {
               "type": "string",
               "minLength": 1,
-              "description": "The manifest file name. Use a .gz or .zst extension to enable transparent decompression (e.g. manifest.json.gz or manifest.json.zst).",
+              "description": "The manifest file name. Only used when a custom storage provider is configured; ignored in CDN mode. Use a .gz or .zst extension (e.g. manifest.json.gz) to enable transparent decompression.",
               "default": "manifest.json"
             },
             "poll_interval": {