v0.3.0

Added

• Every Tacit model call is metered into a local, content-free usage ledger;
  new costHistoryDays, costWarnDailyUsd, costWarnMonthlyUsd. (#33)
• Routes for the ledger and prices, /api/tacit/bootstrap-preview (what a
  bootstrap would cost) and /api/tacit/analyze-batch. (#33)
• Usage and Pricing cards in Settings: spend tiles, a daily chart, spend by
  operation, warnings, a run list, the rate table and the price source. (#33)
• A Data & privacy card with retention, spend warnings and confirm-gated
  clearing; the bootstrap button shows a live cost estimate. (#33)

Changed

• Settings → Tacit is eight collapsible cards instead of one long page. (#33)
• ✨ Improve converges in one pass; improving a finished prompt again returns
  it unchanged. (#31)

Full diff: v0.2.3...v0.3.0