Clarify dependency removal PR policy in AGENTS.md

[alexkroman]

Summary

Updated the dependency management guidance in AGENTS.md to explicitly clarify that removing dependencies requires a dedicated PR, even when the removal is paired with deleting the code that used the dependency.

Changes

• Expanded the dependency change policy to explicitly mention "remove" alongside "add" and "bump"
• Added clarification that dependency removals rewrite uv.lock and therefore warrant their own PR to avoid merge conflicts with feature branches
• Emphasized that this applies even when a dependency removal is coupled with deleting the code that depended on it

Rationale

The original guidance only mentioned adding or bumping dependencies as requiring dedicated PRs. This update makes explicit that the same principle applies to removals, since uv.lock changes are the root cause of merge conflicts — not the semantic nature of the change. This prevents feature branches from colliding in the lockfile when one removes a dependency and another adds one.

https://claude.ai/code/session_01BBoBygev93Rkj1AcowNsjA