Describe kind/location overrides in the README

Author: ileitch

README.md

@@ -350,6 +350,17 @@ Comment commands also support trailing comments following a hyphen so that you c
 class MyClass {}
 ```
 
+### Overriding Result Kind and Location
+
+In generated code scenarios where the generated code is too low-level or obtuse to be directly reported as unused, you can override the `kind` and/or `location` of a result to provide a more meaningful report:
+
+```swift
+// periphery:override kind="MyCustomThing" location="path/to/file.swift:42:1"
+func generatedFunction() {}
+```
+
+The `kind` override allows you to specify a custom kind that will be shown in the result. The `location` override uses the format `file:line:column` (line and column default to 1 if omitted). This is particularly useful when you want to report results at a higher-level definition rather than at the low-level generated code.
+
 ## Xcode Integration
 
 Before setting up Xcode integration, we highly recommend you first get Periphery working in a terminal, as you will be using the same command via Xcode.