fix: add us-cpa tax year rules and package metadata

skills/us-cpa/README.md

@@ -0,0 +1,45 @@
+# us-cpa package
+
+Standalone Python CLI package for the `us-cpa` skill.
+
+## Install
+
+From `skills/us-cpa/`:
+
+```bash
+pip install -e .[dev]
+```
+
+## Run
+
+Installed entry point:
+
+```bash
+us-cpa --help
+```
+
+Repo-local wrapper without installation:
+
+```bash
+scripts/us-cpa --help
+```
+
+Module execution:
+
+```bash
+python3 -m us_cpa.cli --help
+```
+
+## Tests
+
+From `skills/us-cpa/`:
+
+```bash
+PYTHONPATH=src python3 -m unittest
+```
+
+Or with the dev extra installed:
+
+```bash
+python -m unittest
+```