Run oxfmt across repo, add format script and ignore config

Format all non-generated files with oxfmt via `vp fmt`. Add
.oxfmtignore to skip bindings/ and wasm-pack output. Add npm
format script and update DEVELOPMENT.md docs.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

plugins/action-copy-grpcurl/README.md

@@ -37,7 +37,6 @@ The plugin analyzes your gRPC request configuration and generates a properly for
 
 ### Simple Unary Call
 
-
 ```bash
 grpcurl -plaintext \
   -d '{"name": "John Doe"}' \