mark_used, mark_wrong, and decay all modified node state (weight,
uses, wrongs, spaced_repetition_interval) only in memory + state.json.
Like the categorize fix, these changes would be lost on cache rebuild.
Now all three append updated node versions to the capnp log. Decay
appends all nodes in one batch since it touches every node.
Co-Authored-By: Kent Overstreet <kent.overstreet@linux.dev>
categorize() only updated the in-memory HashMap and state.json cache.
When init appended new nodes to nodes.capnp (making it newer than
state.json), the next load() would rebuild from capnp logs and lose
all category assignments.
Fix: append an updated node version to the capnp log when category
changes, so it survives cache rebuilds.
Co-Authored-By: Kent Overstreet <kent.overstreet@linux.dev>
