Stop naming the deleted make serve target
978f2b7 deleted the serve subcommand and its make serve target, but two lines still name the target. The comment above [profile.dev.package."*"] in Cargo.toml says dependencies are optimized in a dev build because make serve runs one, and web/vendor/face-detection/README.md lists make serve among the commands that run scripts/fetch-vendor.sh first, where the Makefile has no such target.
The comment now names make web, which runs that dev build (cargo run -- web, Makefile:106), and the README keeps make build, make web and ./scripts/test.sh, each of which runs fetch-vendor. After the change git grep -n 'make serve' finds nothing. This touches a comment and a README only, so no behavior changes and no test is added.
Validation: ./scripts/test.sh on Ubuntu 24.04 (WSL) passes every gate on this tree, including the browser lane, cargo-audit, cargo-deny and the formatters. Two Python tests were reported as not checked, both for the environment: the run was as root and outside a venv.
Closes #562
Summary by cubic
Stops naming the deleted make serve target in the Cargo.toml dev-build comment and the face-detection vendor README. The comment now credits make web with running the optimized dev build, and the README lists only the commands that actually run scripts/fetch-vendor.sh. No behavior changes.