Implement rollback-safe tree mutations

README.md

@@ -41,6 +41,9 @@ boundary are documented in [`docs/write-domains.md`](docs/write-domains.md).
 Unbiased password generation, character-set validation, in-place replacement,
 and presentation actions are documented in
 [`docs/password-generation.md`](docs/password-generation.md).
+Rollback-safe remove, move, and copy transactions, destination rules, and
+selective subtree reencryption are documented in
+[`docs/tree-mutations.md`](docs/tree-mutations.md).
 
 ## Project layout