Validate and configure the local Salesforce development environment. Runs a prerequisite scan across required tools with per-tool status and offers to install or update missing items. Use when the user asks to 'check my setup', 'validate tools', 'verify prerequisites', 'am I set up correctly', or reports a tool is missing or not working. DO NOT TRIGGER for org auth (/salesforce-development:login), deployment problems (platform-metadata-deploy), or status checks (/salesforce-development:status).
