refactor: use drop-ins for aliases and path management

installers/install_starship.sh

@@ -77,23 +77,15 @@ configure_shell() {
     # Add ~/.local/bin to PATH for the current process
     export PATH="$HOME/.local/bin:$PATH"
 
-    local config_file="$HOME/.bashrc"
-    if [ -f "$config_file" ]; then
-        # Ensure ~/.local/bin is in PATH for this file if not already present
-        if ! grep -q '\.local/bin' "$config_file" 2>/dev/null; then
-            log_info "Adding ~/.local/bin to PATH in $config_file..."
-            local path_content='export PATH="$HOME/.local/bin:$PATH"'
-            inject_block "$config_file" "local-bin path" "$path_content"
-        fi
+    # Clean up legacy in-place configuration blocks
+    IFS=' ' read -ra target_files <<< "$(get_shell_configs)"
+    for config_file in "${target_files[@]}"; do
+        remove_block "$config_file" "local-bin path"
+        remove_block "$config_file" "starship init"
+    done
 
-        log_info "Adding starship initialization to $config_file..."
-        local content='eval "$(starship init bash)"'
-        
-        inject_block "$config_file" "starship init" "$content"
-
-        # Source to apply changes in the current context
-        . "$config_file" 2>/dev/null || true
-    fi
+    write_env_snippet "local-bin" 'export PATH="$HOME/.local/bin:$PATH"'
+    write_env_snippet "starship" 'eval "$(starship init bash)"'
 }
 
 main() {