Logging: per-session file and debug-gated verbose logs

- Open /tmp/hl2hake.log once in the library constructor with "w" so each
  session starts clean, use line buffering, flush each line, and close it via
  atexit. No more fopen/fclose per message.
- Add logd() for verbose diagnostics, enabled only with HL2H_DEBUG=1.
- Move ESP/NPC scans, item-prop/item-classification logs, aimbot/silent-aim/
  melee/triggerbot/spread details, jumpbug tracking, bone dumps, netvar dumps,
  cmd-modified and ground-trace noise to logd().
- Keep logf() for lifecycle, config, warnings/errors, GUI open/close, item
  category/tagging summaries and item-crate detections so crate debugging
  works without the ESP stream.
- Supply crates now respect the max-distance slider (user change), with the
  stale comment and CONTEXT updated.
- Document HL2H_DEBUG=1 in play.sh and CONTEXT.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/hl2h.h b/src/hl2h.h
index cc11e0d..9b4fa8a 100644
--- a/src/hl2h.h
+++ b/src/hl2h.h
@@ -21,6 +21,7 @@ constexpr float PI_F = 3.14159265f;
 // ---------------------------------------------------------------------------
 
 void logf(const char *fmt, ...);
+void logd(const char *fmt, ...); // debug-only (HL2H_DEBUG=1)
 
 // ---------------------------------------------------------------------------
 // on-screen toasts