docs: add v1.2.18 features documentation (#23088)

## Summary
- Added documentation for all new features from Bun v1.2.18 release
- Updates are minimal and concise with high information density
- Includes relevant code examples where helpful

## Updates made

### New features documented:
- ReadableStream convenience methods (`.text()`, `.json()`, `.bytes()`,
`.blob()`)
- WebSocket client permessage-deflate compression support
- NODE_PATH environment variable support for bundler
- bun test exits with code 1 when no tests match filter
- Math.sumPrecise for high-precision floating-point summation

### Version updates:
- Node.js compatibility version updated to v24.3.0
- SQLite version updated to 3.50.2

### Behavior changes:
- fs.glob now matches directories by default (not just files)

## Test plan
- [x] Verified all features are from the v1.2.18 release notes
- [x] Checked documentation follows existing patterns
- [x] Code examples are concise and accurate

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Bot <claude-bot@bun.sh>
Co-authored-by: Claude <noreply@anthropic.com>
Co-authored-by: Jarred Sumner <jarred@jarredsumner.com>

docs/bundler/index.md

@@ -313,6 +313,14 @@ $ bun build --entrypoints ./index.ts --outdir ./out --target browser
 
 Depending on the target, Bun will apply different module resolution rules and optimizations.
 
+### Module resolution
+
+Bun supports the `NODE_PATH` environment variable for additional module resolution paths:
+
+```bash
+NODE_PATH=./src bun build ./entry.js --outdir ./dist
+```
+
 <!-- - Module resolution. For example, when bundling for the browser, Bun will prioritize the `"browser"` export condition when resolving imports. An error will be thrown if any Node.js or Bun built-ins are imported or used, e.g. `node:fs` or `Bun.serve`. -->
 
 {% table %}