Enable Biome's `organizeImports` with groups matching the original
ESLint `import/order` configuration:
1. **Node builtins** (`node:fs`, `path`, etc.)
2. *(blank line)*
3. **Third-party packages** (`express`, `@sentry/node`, etc.)
4. *(blank line)*
5. **Local/relative imports** (`../foo.js`, `./bar.js`, aliases)
This resolves the inconsistency where Biome wasn't enforcing import
grouping, meaning new files would lose the blank-line separation that
the old ESLint config enforced.
### Impact
- **354 files** updated out of 738 checked (~48%)
- **+188 / -240 lines** (net -52) — almost entirely single blank line
additions/removals between import groups
- No import reordering; purely group separator consistency
Fixes#7373🤖 Generated by LLM (Claude, via OpenClaw)
