Record solver weight tuning results

docs/compaction-handoff.md

@@ -1,6 +1,34 @@
 # Compaction Handoff
 
-Current date/time context: 2026-06-26, local timezone America/Chicago.
+Current date/time context: 2026-06-27, local timezone America/Chicago.
+
+## 2026-06-27 Tuning Status And Safe Installed State
+
+- The mod is disabled on disk for the next game launch. Active
+  `EdgeWeightGPS.dll` was renamed to
+  `EdgeWeightGPS.live-tunable-92287bd.dll.disabled` in the Cyberpunk RED4ext
+  plugin directory. `solver_weights.bin` was reset to vanilla `1.0`.
+- This does not unload the DLL from a currently running game process; it only
+  guarantees the next cold start has no active EdgeWeightGPS plugin.
+- Latest committed live-tunable solver patch before this note:
+  `92287bd Add live-tunable GPS solver highway weight`.
+- Live tuning results from the El Coyote / city-center route set:
+  - `0.80`: plugin loaded and patched, but route handles were identical to
+    vanilla for side job and Claire; Sinnerman/custom changed only packed
+    metadata on the same handles.
+  - `0.70`: still effectively identical at the handle level. Side and Claire
+    matched vanilla/0.80; Sinnerman and custom were metadata-only changes.
+  - `0.55`: visibly crossed the threshold. User reported the custom pin did the
+    funky city-center hairpin again. Archived log shows post-reload route
+    records changing into 37-49 record alternatives, not just metadata tweaks.
+- Interpretation: the useful tuning threshold for this start/target set is
+  between `0.70` and `0.55`, but `0.55` is already too aggressive for at least
+  the custom pin. Next candidate should be around `0.62` or `0.65`, then test a
+  wider set of long routes before choosing a default.
+- New evidence logs:
+  `logs/EdgeWeightGPS_solver080_3548.log`,
+  `logs/EdgeWeightGPS_solver070_3900.log`,
+  `logs/EdgeWeightGPS_solver055_hairpin_4156.log`.
 
 ## 2026-06-26 Confirmed Solver-Cost Patch
 
@@ -20,7 +48,7 @@ Current date/time context: 2026-06-26, local timezone America/Chicago.
   obviously different route choices. User confirmed the custom pin returned to
   the straight city-center roundabout route, while the `0.35` build took the
   wrong hairpin.
-- Current installed build enables the inline patch with default highway
+- The live-tunable build enables the inline patch with default highway
   multiplier `0.80` and polls
   `red4ext/plugins/EdgeWeightGPS/solver_weights.bin` every 500 ms. The file is
   exactly one little-endian float32 highway multiplier.