refactor: use drop-ins for aliases and path management

installers/install_nvim.sh

@@ -106,24 +106,27 @@ install_config() {
 }
 
 configure_shell() {
+    # Clean up legacy inline edits from bashrc and bash_aliases
     IFS=' ' read -ra target_files <<< "$(get_shell_configs)"
-
     for config_file in "${target_files[@]}"; do
-        local modified=false
-
-        if add_alias_if_missing "$config_file" "vim" "nvim"; then
-            modified=true
-        fi
-
-        if add_env_if_missing "$config_file" "EDITOR" "nvim"; then
-            modified=true
-        fi
-
-        # Source if modified (only for bashrc, and not when sourced to prevent recursion)
-        if [ "$modified" = true ] && [ "$config_file" = "$HOME/.bashrc" ]; then
-            . "$config_file" 2>/dev/null || true
+        if [ -f "$config_file" ]; then
+            local tmp_file
+            tmp_file=$(mktemp)
+            sed '/^export EDITOR="nvim"/d' "$config_file" > "$tmp_file"
+            cat "$tmp_file" > "$config_file"
+            rm -f "$tmp_file"
         fi
     done
+    if [ -f "$HOME/.bash_aliases" ]; then
+        local tmp_file
+        tmp_file=$(mktemp)
+        sed '/^alias vim="nvim"/d' "$HOME/.bash_aliases" > "$tmp_file"
+        cat "$tmp_file" > "$HOME/.bash_aliases"
+        rm -f "$tmp_file"
+    fi
+
+    write_alias_snippet "nvim" 'alias vim="nvim"'
+    write_env_snippet "nvim" 'export EDITOR="nvim"'
 }
 
 main() {