feat: coordinate causal host publications

[developer-1px]

Summary

• add a synchronous host Adapter that flushes pending input before ready-time materialization, journals sequence-ordered host publications, and fails closed on protocol or publication-order violations
• add inbox-local journal revisions with direct suffix indexing, dependency revision validation, and single-copy projection logging
• extend positional, stable-id, and causal selection handoff from Pointer to one SelectionPoint while preserving pointer-only declaration compatibility

Performance

The new perf:causal benchmark compares explicit revision suffixes with the legacy full-journal path. On the local default 10k journal run:

• baseRevision suffix 0: p50 0.034ms, p90 0.049ms
• baseRevision suffix 10: p50 0.045ms, p90 0.046ms
• legacy full journal: p50 10.851ms, p90 12.818ms

The benchmark is observational and non-gating.

Verification

• patch-rebase verify: 21 tests
• stable-id-rebase verify: 18 tests
• causal-patch-inbox verify: 57 tests
• full extension lab evaluation: 41 packages
• docs evaluation
• core typecheck
• independent final code review: no blocking findings

Compatibility

The published JSONDocument core interface is unchanged. Hostless causal behavior and Pointer runtime shapes remain intact. Pointer-only Parameters and ReturnType utility consumers are locked by declaration tests; SelectionPoint support is additive in the private lab packages.