Misc fixes and improvements

* Added request logging to com.noccy.apiclient
* Added plugin com.noccy.watcher
* Added pipe command and filter support
* Fixes and stubs

runtime/functions.php

@@ -81,3 +81,25 @@ function read_config($file=null) {
     }
     return (array)json_decode(file_get_contents($abs), true);
 }
+
+
+// ------ Filters ------
+
+$FILTERS = [];
+
+function register_filter(string $name, callable $filter) {
+    global $FILTERS;
+    $FILTERS[$name] = $filter;
+}
+
+function get_registered_filters(): array
+{
+    global $FILTERS;
+    return array_keys($FILTERS);
+}
+
+function get_filter(string $name): ?callable
+{
+    global $FILTERS;
+    return $FILTERS[$name]??null;
+}