0.3.1 — three chapters: reports, GitHub as an introduction, and the whole lifecycle

• Reports. A milestone's narration becomes part of the board: taskops_activity
  reads the whole story of N cards at once, taskops_filed records a report as
  {path, title, milestone, sha} — the CONTENT stays a file in .taskops/reports/
  and the list is a fold over the log, never a table. The dashboard lists a
  milestone's reports and renders one in a sandboxed iframe, served by a read-only
  /git door that hands back a committed file at a rev.
• GitHub is the INTRODUCTION, never the credential. taskops join <board> --github enrols your ssh key when you have push on the repo the board declared.
  The token is asked for once, travels in one request body, and is stored nowhere;
  what persists is a pubkey. A board opts in with taskops board forge <owner>/<repo> and opts back out with --clear — owner only, both ways. Absent
  a forge (how every board is born) that door does not exist.
• The lifecycle runs backwards too. taskops board pull brings a hosted board
  down as a snapshot — the same five steps as push, in reverse, over paging — and
  taskops board rm takes one off a host. rm REFUSES to destroy a history this
  checkout does not hold, judged on the host against the board's real event ids,
  and says which of the two ways out you want. There is no --force and
  --discard-history is not an alias for one.
• Fixed: the dashboard flooded a remote board with requests. The forward
  published a change frame on any answer carrying a seq, and every envelope
  carries one — so every READ announced a change, the page refetched, and the loop
  ran at coalesce speed. Reads no longer poke anybody.
• The taskops ui window is a lease, not a pidfile. A flock that dies with
  its holder, an identity check on /healthz before a browser is reopened, and a
  server that retires itself when no tab has been open for thirty minutes.
• Fixed: a minted secret can no longer start with -, which made roughly one
  invite in 64 unusable as a CLI flag value.
• A client that hangs up mid-response is no longer printed as a crash.