v0.3.0

Added

• tools webrain_page_info —
  just-in-time page context (viewport/page size, scroll position,
  pixels/pages above & below, position %) so the LLM knows when to scroll.
• tools --state/--restore:
  webrain_save_state / webrain_restore_state — export/import a profile's
  auth state (cookies + localStorage) to state.json so logins follow you
  across machines.
• cli: webrain -v / --version / version prints the version.

Fixed

• core: webrain install failed with "the response body is larger than
  request limit" — ureq's read_to_vec() caps bodies at 10 MB, too small for
  the Chrome/Obscura engine zips. Now reads via the unlimited
  into_with_config() reader.

Changed

• docs: rewrote README — removed the table of contents and made it
  install-first with a "Why webrain?" comparison and a use-case section;
  added the Scoop extras install option.
• build: moved the Dockerfile into docker/ and added
  docker/docker-compose.yml (webrain MCP server + persistent
  vault/profile/cache volumes).
• tools: deduped the repeated JS→JSON parse chain in tools.rs into
  parse_json_str / arr_len helpers — no behavior change.