Seed LTM environments from previously accumulated count tables

Converts a list of data.tables (the output format of count_tables) back into sparse environments so that update_env_and_build_stm_tables can continue accumulating counts on top of them.

Usage

apply_prior_ltm(counts_ltm, prior, N)

Arguments

counts_ltm

List of environments (one per order 0..N)

prior

List of data.tables from a previous count_tables() call

N

Maximum n-gram order

Value

counts_ltm with prior counts loaded into the environments

Details

Only symbols with Ce > 0 are stored as environment keys. This is critical: `update_env_and_build_stm_tables` uses `sym whether a symbol was already "seen" in a context, which controls the ltm_update_exclusion early-stop logic. Storing Ce = 0 entries as keys would cause false "already seen" hits and premature stopping.