Initial commit: AI conversation impact methodology and toolkit

CC0-licensed methodology for estimating the environmental and social
costs of AI conversations (20+ categories), plus a reusable toolkit
for automated impact tracking in Claude Code sessions.

tasks/04-tooling-readme.md

@@ -0,0 +1,22 @@
+# Task 4: Write tooling README
+
+**Plan**: reusable-impact-tooling
+**Status**: DONE
+**Depends on**: Task 3 (need final directory structure)
+**Deliverable**: README for the impact toolkit
+
+## What to do
+
+1. Write a README covering:
+   - What the toolkit does (tracks energy, CO2, cost per conversation).
+   - How to install (run `install.sh`).
+   - What gets measured and how (brief summary with pointer to methodology).
+   - How to view results (`show-impact.sh`).
+   - Known limitations (estimates, not measurements).
+   - Dependencies (`jq`, `bash`, Claude Code with hooks support).
+
+2. Keep it short. Under 100 lines.
+
+## Done when
+
+- A new user can understand and install the toolkit from the README alone.