chore: update changeset for v3.25.18 with latest PRs

Author: mrubens

.changeset/v3.25.18.md renamed to .changeset/v3.25.18-2.md

@@ -6,3 +6,4 @@
 - Fix: prevent duplicate LM Studio models with case-insensitive deduplication (#6954 by @fbuechler, PR by @daniel-lxs)
 - Add support for Sonic model (thanks @mrubens!)
 - Feat: simplify ask_followup_question prompt documentation (thanks @daniel-lxs!)
+- Feat: simple read_file tool for single-file-only models (thanks @daniel-lxs!)