Record what a history publication means instead of inferring it from row shapes #3870

Part of #3868 (follow-ups to #854).

DetachedHistoryPublication.publish (packages/core/src/services/history/detachedHistoryPublication.ts) decides what to write to the session recording by comparing the old and new rows:

• value-identical rebuild: nothing
• strict deep-equal prefix: one rewind {itemsRemoved, cutSeq}
• one summary replacing an all-marked journal: compressionDetail plus compressed
• anything else: full rewind plus content

The shapes are covered by detached-publication-shapes.test.ts, so the recordings are correct today. The design question is whether callers should declare their intent (cut, compression, clear, replace) so the recorder writes the matching record directly. Inferring intent from shapes means a new caller can get a different record type than it meant, and the comparison costs a streamed pass over both journals on every publication.

Proposed

Add an explicit intent to the publication call, derive the record from it, and keep the shape comparison only as an assertion in tests. This also simplifies per-origin fan-out translation (#3865), since each record would carry its meaning.