lattice diff --raw: show actual git diff of .lattice/ files

[gmoon]

Problem

lattice diff only shows a semantic summary (added/modified/resolved/deleted nodes). Sometimes you need to see the actual YAML changes — for reviewing exact field modifications, piping into other tools, or applying patches.

Solution

Add a --raw flag to lattice diff that outputs the raw git diff of .lattice/ files since the base ref.

# Show raw git diff of lattice files
lattice diff --raw

# With a specific ref
lattice diff --raw --since HEAD~5

Output is uncolored and machine-consumable, suitable for piping into git apply, delta, or other diff tools.

Status

Implemented in PR #19.