v0.3.0 — Leads & funnels

Leads & funnels, opt-in per project.

• A lead is its own entity with per-project funnel stages (OPEN / WON / LOST),
  custom fields validated into leads.data, an append-only journal with
  comments and a linked task for the work it needs. Moving a lead to a LOST
  stage requires a reason.
• Presets on enable: sales (new → qualification → proposal sent →
  negotiation → audit paid → won / lost), orders (new → confirmed → driver
  assigned → done → paid / cancelled) and basic. Stages and fields stay
  editable afterwards.
• Lead intake: POST /ingest/leads with a per-project X-Lead-Token (sha256
  in the database, the value is shown once). Idempotent on source +
  external_id; a repeat can move the stage or, with update: true, update
  fields. Values that don't match the field schema land in data._extra
  instead of being rejected.
• Board with drag & drop, table with search and filters, funnel stats
  (/projects/{id}/leads/stats), short lead links /l/<key>, funnel settings
  page with stages, fields and ingest keys.
• Permissions: lead.view / lead.manage for project members,
  lead.delete for managers, lead.settings for project owners.
• CLI: pms.py lead list|add|show|stage|edit|comment|task|stats|enable|tokens|token-add|ingest.
• Migration d4e5f6a7b8c9. Next.js 15.5.28.

Full history: CHANGELOG.md