chore: add .prettierignore so editor formatting skips generated and vendored files (Closes #48)

.prettierignore

@@ -0,0 +1,75 @@
+# Prettier ignore rules.
+#
+# Prettier is not a build dependency in this repo; it reaches contributors
+# through the `esbenp.prettier-vscode` extension installed by
+# .devcontainer/devcontainer.json. Without this file, "Format Document" and
+# format-on-save happily rewrite generated, vendored and binary-adjacent files
+# that are not ours to reformat, producing large unrelated diffs in PRs.
+#
+# Mirrors .gitignore / .dockerignore where the same paths apply.
+
+# Dependencies
+node_modules/
+frontend/node_modules/
+backend/node_modules/
+
+# Lockfiles — regenerated by npm, never hand-formatted
+package-lock.json
+frontend/package-lock.json
+backend/package-lock.json
+
+# Build output
+frontend/dist/
+backend/dist/
+playwright-report/
+test-results/
+builds/output/
+builds/test-output/
+builds/ila-repo/
+
+# Logs
+build.log
+*.log
+
+# Local environment / runtime data
+.env
+.env.local
+.env.*.local
+.env.production
+backend/.env
+backend/.env.local
+backend/.env.*.local
+frontend/.env.local
+frontend/.env.*.local
+.proofdesk-data/
+backend/.proofdesk-data/
+.tmp/
+
+# Prisma-managed artifacts and the local dev database
+backend/prisma/migrations/
+backend/dev.db
+backend/dev.db-journal
+*.db
+*.sqlite
+*.sqlite3
+
+# Vendored PreTeXt fixture repository — upstream content, not ours to format
+test-repo/
+
+# Generated coverage
+coverage/
+
+# Binary / non-formattable assets
+*.png
+*.jpg
+*.jpeg
+*.gif
+*.svg
+*.ico
+*.woff
+*.woff2
+*.ttf
+*.eot
+*.pdf
+*.zip
+*.tgz