chore: clean hydrotech-beam syncthing conflicts and add new docs

- Remove all .sync-conflict-* files
- Remove temp _temp_part_properties.json files
- Add USER_GUIDE.md
- Add dashboard docs (Executive, Technical, Operations, Master Plan)
- Add playbooks (DOE, NX_REAL_RUN, SYNCTHING_RECOVERY)
- Update iteration results

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

projects/hydrotech-beam/playbooks/SYNCTHING_RECOVERY.md

@@ -0,0 +1,38 @@
+# Playbook — Syncthing Recovery (Hydrotech Beam)
+
+## Symptoms
+- Latest run not visible on other side
+- Old timestamps persist remotely
+- `*.sync-conflict-*` files appear in `results/`
+
+## Recovery steps
+1. Confirm both sides point to the same folder path
+2. Rescan folder in Syncthing GUI
+3. Pause/resume folder if stale
+4. Restart Syncthing if needed
+5. Archive conflicts from active results root
+
+## Conflict archive snippet (PowerShell)
+```powershell
+$ts = Get-Date -Format "yyyyMMdd_HHmmss"
+$archive = ".\results\archive_conflicts_$ts"
+New-Item -ItemType Directory -Path $archive -Force | Out-Null
+Get-ChildItem .\results -File -Filter "*.sync-conflict-*" | Move-Item -Destination $archive
+```
+
+## Clean rerun prep snippet (PowerShell)
+```powershell
+$ts = Get-Date -Format "yyyyMMdd_HHmmss"
+$old = ".\results\archive_before_clean_rerun_$ts"
+New-Item -ItemType Directory -Path $old -Force | Out-Null
+
+$toArchive = @("doe_results.csv","doe_summary.json","doe_run.log","history.csv","history.db","optuna_study.db")
+foreach ($f in $toArchive) {
+  if (Test-Path ".\results\$f") { Move-Item ".\results\$f" $old }
+}
+```
+
+## Verification
+- Main `results/` has only current active artifacts
+- Conflict files moved to archive folder
+- Remote side sees same timestamps/files