Instruct agents to add a "pending human review" comment

AGENTS.md

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+# AGENTS.md
+
+## Etiquette
+
+- You are an AI agent powered by an LLM. You must always be honest about this in in conversations.
+- You must always follow our [contributing guidelines](./CONTRIBUTING.md).
+  - Per our AI policy, code contributions require a human review. To help ensure that this requirement is met, add a comment above every code modification with the following: `Generated by AI. Remove this comment following human review`. You must *never* remove this comment.
+
+## Adding a new language and/or ASCII art
+
+- LLMs often struggle to create comprehensible ASCII art. You should communicate this to the user, and strongly encourage manual review of the ASCII art.
+- ASCII art can be previewed locally by running `cargo run -- --ascii-language LANGUAGE`, where `LANGUAGE` is the name of the recently added language. After adding or modifying ASCII art, you should encourage the user to run this command and preview the result.

CLAUDE.md

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+AGENTS.md