Seeds: scope compiler_options to seed run, restore in after

Remove global ignore_module_conflict from mix.exs. Set it only in
seeds.exs during eval_file and restore via try/after so crashes
do not leave the option enabled.

mix.exs

@@ -2,8 +2,6 @@ defmodule Mv.MixProject do
   use Mix.Project
 
   def project do
-    Code.compiler_options(ignore_module_conflict: true)
-
     [
       app: :mv,
       version: "0.1.0",

priv/repo/seeds.exs

@@ -4,9 +4,15 @@
 #
 # Bootstrap runs in all environments. Dev seeds (members, groups, sample data)
 # run only in dev and test.
+#
+# Compiler option ignore_module_conflict is set only during seed evaluation
+# so that eval_file of bootstrap/dev does not emit "redefining module" warnings;
+# it is always restored in `after` to avoid hiding real conflicts elsewhere.
 
+prev = Code.compiler_options()
 Code.compiler_options(ignore_module_conflict: true)
 
+try do
   # Always run bootstrap (fee types, custom fields, roles, admin, system user, settings)
   Code.eval_file("priv/repo/seeds_bootstrap.exs")
 
@@ -16,4 +22,6 @@ if Mix.env() in [:dev, :test] do
   end
 
   IO.puts("✅ All seeds completed.")
-Code.compiler_options(ignore_module_conflict: false)
+after
+  Code.compiler_options(prev)
+end