Rename leftovers in UI copy and paths after the tools/catalog renames #8

The repos were renamed: benchmark-tool → tools-benchmark (ADR 0005) and ssg-frameworks → catalog-ssg (ADR 0001). #7 updated the docs and the submodule URLs. Still to do:

• UI copy and links in src/sections/{Intro,Rounds,Environment}.svelte, and the e2e test tests/e2e/sections.spec.js.
• Submodule paths data/benchmark-tool and data/ssg-frameworks. Renaming them to data/tools-benchmark and data/catalog-ssg means changing scripts/build-data.mjs too.
• package.json references.