Single model_memory_mb field now serves as the sole source of truth for
base model memory. Removes the redundant base_model_memory_mb field,
legacy dual-path branches in calculate_optimal_batch_size() and
max_safe_batch_size(), and the associated legacy test.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Move 17 library crates into crates/, CLI binary into bin/fxt,
consolidate 10 test crates into testing/, split config crate
from deployment config files.
Root directory reduced from 38+ to ~17 directories.
All Cargo.toml paths and build.rs proto refs updated.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>