wiki-fold: Extractive Log Rollup

Implements a bounded subset of Mechanism 1 from [[DragonScale Memory]]: flat fold over raw wiki/log.md entries. Fold-of-folds (hierarchical level-stacking) is out of scope for this skill; see "Scope boundary" below.

A fold is additive: child log entries and their referenced pages are never modified, moved, or deleted. A fold is extractive: every outcome and theme in the output must be traceable to a specific child log entry. No invented facts, no synthesis beyond what the child entries support.

Scope boundary (explicit)

This skill does not implement:

• Fold-of-folds / hierarchical level stacking (DragonScale spec calls for it; deferred to a future skill).
• Automatic triggering (folds are always human-invoked in Phase 1).
• Semantic-tiling dedup (Mechanism 3; separate skill).

It does implement:

• Flat fold over raw log.md entries at a chosen batch exponent k.
• Structural idempotency via a deterministic fold ID.
• Extractive summarization with count-checking.