v0.1.4 — Token savings stats

What's new

After each matched prompt, open-context now appends a token savings line
to the injected context:

[open-context] 91% token reduction (1.2 KB injected vs 14.8 KB full context)

The baseline is format_report() run across all domains (no threshold filter),
giving a concrete all-domain ceiling to compare against.
Stats are best-effort — a failure never breaks context injection.

Changes

• resolver.py — new include_all_domains keyword-only param on resolve()
  for the baseline pass
• resolve_hook.py — computes and appends savings stats after truncation
• 5 new integration tests: presence, numeric sanity, no-match guard,
  truncation survivability, superset contract