Support max_source_rows and max_source_bytes limits #8234

Why

On large datasets compaction has to run incrementally — no single run can afford to
rewrite everything at once. Today the only knob for that is max_source_fragments.
It works well when fragments are similarly sized, but fragment sizes can vary a lot
in practice (a fragment may hold a handful of live rows or millions), so the same
fragment budget may translate into very different amounts of IO and rewrite time
across runs. Row- and byte-based budgets make the per-run workload easier to predict.

What

Add two planning budgets to CompactionOptions that complement max_source_fragments
by bounding a single run on the data volume dimension:

• max_source_rows — counted as live rows (physical rows minus soft-deleted rows).
• max_source_bytes — total size of the source fragments' data and overlay files,
  read from sizes recorded in the manifest (no object-store metadata round trips).
  Deletion files and files that only back dropped columns are not counted.

Behavior:

• All configured max_source_* limits apply together: tasks are admitted in order
  until adding the next task would exceed any one of them.
• The limits are hard upper bounds: if the first task already exceeds a budget the
  plan is empty and a warning is logged.
• A budget of zero is rejected (None means no limit); validation is centralized in
  CompactionOptions::validate.

Exposed in Rust / Python / Java, plus the manifest config keys
lance.compaction.max_source_rows and lance.compaction.max_source_bytes.