cleanup-defensive

Remove try/catch and defensive null-checks that don't serve a real role. The goal is errors that propagate cleanly to the boundary that knows how to handle them, not silent fallbacks that hide bugs. **Core principle**: catch only when you can do something more useful than the default propagation — and "log and rethrow" is rarely more useful than just letting it throw. ## Preflight 1. **Language detect**: TS/JS, Python, Go (`if err != nil` patterns), Rust (`unwrap_or`/`map_err` chains that smell defensive). 2. **Git state**: refuse on dirty tree. 3. **Report dir**: ensure exists. 4. **Identify boundary files** — preserve catches in: - HTTP request handlers (`app/api/`, `routes/`, Hono/Express/FastAPI handlers) - CLI entry points (files with `if __name__ == "__main__"`, `bin/*`, `cmd/*`) - Message/queue consumers (worker entry points, cron handlers) - Test files (test runners need failures localized) ## Detect ### TypeScript / JavaScript ```bash # Find every try/catch grep -rn --include="*.ts" --include="*.tsx" --include="*.js" -B1 -A5 "try {" \ --exclude-dir=node_modules --exclude-dir=.next . > /tmp/try-catches.txt # ESLint can flag the obvious useless ones npx eslint --rule '{"no-useless-catch": "error"}' --no-eslintrc . 2>&1 | grep no-useless-catch > /tmp/useless-catch.txt ``` Categorize each catch block by content: - **Rethrow only**: `catch (e) { throw e }` or `catch (e) { throw new Error(...) }` with no context added - **Swallow + null/empty return**:...