docs: update roadmap

docs/roadmap.md

@@ -3,6 +3,8 @@
 
 - [ ] **docs**: document simple state machine and how to use `mkunion` for it
 - [x] **feature**: `mkunion watch ./...` command that watches for changes in files and runs faster than `go generate ./...`
+- [x] **feature**: `go:tag mkmatch` to generate pattern matching functions
+- [ ] **docs**: document how to write custom pattern matching functions
 - [ ] **docs**: document other packages in `x/` directory
 - [ ] **docs**: document typescript types generation and end-to-end typs concepts (from backend to frontend)
 - [ ] **feature**: expose functions to extract `go:tag` metadata