resource policy trusted destinations (#875)

* **New Features**
  * Added a Resource Policy editor for each input, supporting trusted hostnames and private network ranges.
  * Resource URLs now retain their source input and use authenticated links where supported.
  * Resource caching is scoped to the policy authorizing access.

* **Bug Fixes**
  * Invalid or unsupported resource values are safely discarded.
  * Redirects and destination addresses are rechecked against the applicable policy.

* **Breaking Changes**
  * Private DNS destinations require approved hosts and networks; private IP literals require an approved network.
  * Input and alias names must be non-empty and globally unique.

backend/processing/src/processor/playlist/tests.rs

@@ -1563,6 +1563,7 @@ mod mapping_stage {
                         match_names: vec!["BBC One".intern()],
                         config: Box::new(IcsEpgSourceConfig::default()),
                     },
+                    input_name: None,
                 }]);
 
                 let mut playlist = FetchedPlaylist {
@@ -1658,6 +1659,7 @@ match {
                         match_names: vec![],
                         config: Box::new(IcsEpgSourceConfig::default()),
                     },
+                    input_name: None,
                 }]);
                 let mut playlist = FetchedPlaylist {
                     input: &input,