Fix dualpath propagation, getShopfloorPCs filtering, USB management, and printer features

- Fix dualpath PC propagation direction (Equipment->PC) in api.asp and db_helpers.asp
- Fix early exit in CreatePCMachineRelationship preventing propagation
- Fix getShopfloorPCs to filter machinetypeid IN (33,34,35) instead of >= 33
- Fix getShopfloorPCs to show equipment numbers via GROUP_CONCAT subquery
- Add detailed PropagateDP logging for dualpath debugging
- Default "Show on Shopfloor Dashboard" checkbox to checked in addnotification.asp
- Add USB label batch printing, single USB labels, and USB history pages
- Add printer supplies tracking and toner report enhancements
- Add uptime map visualization page
- Add dashboard/lobby display SQL migration
- Update CLAUDE.md with IIS 401 workaround documentation
- Update TODO.md

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CLAUDE.md

@@ -154,6 +154,31 @@ PCs are in the machines table, identified by:
 - `pctypeid IS NOT NULL`
 - `machinetypeid IN (33, 34, 35)`
 
+### IIS 401 Error on New ASP Files
+
+**Problem:** When creating new ASP files from scratch, they may return HTTP 200 on the first request but HTTP 401 Unauthorized on all subsequent requests.
+
+**Symptoms:**
+- First curl/browser request to new .asp file returns 200
+- All following requests return 401 Unauthorized
+- Existing files (like printerqrbatch.asp) work fine with consistent 200 responses
+- Adding `<%@ Language=VBScript %>` directive alone does NOT fix it
+
+**Solution:** Instead of creating new ASP files from scratch, **copy an existing working ASP file** to the new filename, then modify its contents:
+
+```bash
+# DON'T do this (creates file from scratch - will get 401 errors):
+# Write tool to create newfile.asp
+
+# DO this instead (copy existing working file):
+cp printerqrbatch.asp newfile.asp
+# Then use Edit tool to replace the content
+```
+
+**Why this works:** The exact root cause is unclear, but appears related to how IIS handles file metadata/permissions for newly created files vs. copied files. Copying preserves whatever attributes IIS needs to serve the file correctly.
+
+**Verified fix:** Files created by copying printerqrbatch.asp consistently return 200 on multiple sequential requests.
+
 ## API Endpoints
 
 **Base URL:** `http://192.168.122.151:8080/api.asp`