v0.1.6

v0.1.6 — output quality: eight fix rounds, semantic errors halved

• Real local-variable names from debug_info; true enum declarations.
• Name-collision classes eliminated (nested chains, sanitizer
  collapses, covariant overrides, package-leaf shadowing — alone
  -12.5k "cannot find symbol" on reqable).
• null/long/cast/super correctness fixes; directional type evidence.
• Full-javac gate (with android.jar) on reqable: 42,251 -> 21,193
  semantic errors (-49.9%). Syntax gate stays at zero across the
  1.18M-file corpus; output deterministic; performance unchanged.
• jdc-core 0.2.1.

Full Changelog: v0.1.5...v0.1.6