ContextLattice v3.16.1 - Compact Means Compact

The Agent Packet made retrieval compact. This patch closes the loop: ordinary
lifecycle commands now stay compact too.

What changed

• contextlattice remember returns a bounded checkpoint receipt instead of the
  recursive write and session adapter envelope.
• contextlattice finish returns a bounded completion receipt with terminal
  state and compact outcome identity instead of full rollups.
• --full remains the explicit escape hatch for debugging and compatibility.
• contextlattice_agent_adapter checkpoint|complete keeps its established full
  response contract for integrations that depend on it.
• contextlattice_lifecycle_receipt.v1 is registered, generated into Go, Rust,
  and the native CLI, and constrained to 4,096 serialized bytes.

Why it matters

An agent should not spend a fresh prompt digesting the machinery that merely
confirmed its previous write. The receipt now carries only what can change the
next move: operation status, session identity, bounded event identity,
checkpoint location, and compact outcome metadata.

Proof

The regression holdout injects 75,000 bytes of backend-only data into both the
memory-write and session-event responses. The primary CLI returns:

• remember: 873 bytes
• finish: 811 bytes
• leaked backend payload: zero bytes

The same holdout proves that --full and the advanced adapter command still
return universal_agent_adapter_response.v1.

Verification includes focused ten-run Go tests, the full gateway suite, Go vet,
generated-contract drift checks, the shared output-contract audit, Rust
contract tests, open-core boundary checks, public leak checks, and live CLI
readback.