chore(claude-code): pin coder-utils to release/coder/coder-utils/v1.2.0

v1.2.0 of coder-utils (#870) is the first release that nests logs under
${module_directory}/logs/, matching the $HOME/.coder-modules/coder/claude-code/logs/
paths documented and tested in this module. Move the source ref off the
feature branch and onto the release tag now that it has shipped.

The registry proxy at registry.coder.com does not yet index v1.2.0, so
keep the git:: source for now and swap to the HCP-style source in a
follow-up once indexing catches up.

Author: matifali

registry/coder/modules/claude-code/main.tf

@@ -169,7 +169,7 @@ locals {
 }
 
 module "coder_utils" {
-  source = "git::https://github.com/coder/registry.git//registry/coder/modules/coder-utils?ref=feat/coder-utils-nest-logs"
+  source = "git::https://github.com/coder/registry.git//registry/coder/modules/coder-utils?ref=release/coder/coder-utils/v1.2.0"
 
   agent_id            = var.agent_id
   agent_name          = "claude-code"