[rbowen]

Closes #357

package.json listed a dependency named - ("-": "^0.0.1"), most likely
added by accident. Nothing in the site imports it.

Newer pnpm releases reject - as a dependency name
(ERR_PNPM_INVALID_DEPENDENCY_NAME), so pnpm install fails for anyone not
on pnpm 9.

This PR:

• Removes "-" from package.json
• Removes the three corresponding - / -@0.0.1 entries from
  pnpm-lock.yaml, edited by hand so that no other lockfile entries change

Tested:

• npx pnpm@9 install --frozen-lockfile succeeds and leaves the lockfile unchanged
• npx pnpm@9 build succeeds (en and zh-CN)