v0.7.0: proof-carrying execution

[renezander030]

Release: v0.7.0

This release makes every accepted action carry durable, inspectable proof from admission through execution.

What changed

• Bind approvals to immutable action IDs, exact payloads, policy digests, and expiry windows.
• Authenticate every tool-gate ask, poll, and consume route with the webhook bearer boundary; signed POST bodies follow webhook.require_signature.
• Turn allowed tool decisions into atomic consume-once permits. Only the first valid consume response carries permit: execute.
• Persist stable action IDs and idempotent terminal state in SQLite; matching retries return the existing result and drift gets 409.
• Write webhook admission records before HTTP 202, return an admission ID, and expose authenticated status polling.
• Add backward-compatible receipt schema v2 while preserving verification of existing v1 rows.
• Add draftcat receipts list, show, and chronological JSONL export from the SQLite source of truth.
• Add ordered model input/output policy rules with fail-closed deny and human review actions.
• Add /healthz liveness and SQLite-backed /readyz readiness endpoints.

Compatibility

• Existing v1 approval receipts continue to verify.
• Existing tool-gate callers receive a generated action ID, but retry-safe clients should send and persist their own stable action_id.
• An allow decision no longer authorizes execution by itself. Clients must consume the returned binding and execute only when the response contains permit: execute.

Validation

• go test ./...
• go test -race ./...
• go test -short ./...
• go vet ./...
• golangci-lint run --new-from-rev=HEAD
• go build .
• draftcat validate --config config.yaml (0 errors)
• v0.6-style SQLite migration regression test