docs: record Highway 21 alarm source audit and well mapping

HANDOFF.md

@@ -1,5 +1,9 @@
 # Current handoff
 
+## Highway 21 card fault source audit — October 26, 2026
+
+Read shared instructions and cloud index; no existing Highway 21 guide. Created HIGHWAY-21-GUIDE.md and cloud guide https://chatgpt.com/space/page_068c2a277110819180a2c5853c714e99, indexed both. User mapping recorded, including index10 Well18 and index11 Well19. Water catalog2,766 registers; card search zero; unlatched170; fault60 VFD entries. Exact inspected flow fault source Application.GVL.Well[0].out.flow.flt.chan.unlatched is disabled, On Change1s. Water has26 alarms. Existing index10/11 low-flow/low-level descriptions swap Well19/18 relative to user mapping; retained. Requested fault.card.unlatched addition awaits clarification of new tags versus existing channel faults. No site configuration or PLC values saved. Next: resolve exact sources, add/verify alarms, update guides and commit completion.
+
 ## Coop ventilation and water-flow alarm groups — October 24, 2026
 
 Added three native compact equipment sections to Mandel page_alarms: Chicken Coop · Temperature (g_coopTemp, C), Ventilation · Negative Air Pressure (g_negAirPres, Pa), Water Flow · House (g_houseFlow, gpm). Each reuses four LL/L/H/HH limit/reset/limit-enable/alarm-enable/state rows and three sensor fault enable/state pairs. Coop additionally exposes thermistor sensorFault_in_en/out. Existing settings preserved: coop0/0/30/35C, ventilation0/0/50/100Pa, flow0/0/15/20gpm; all reset gaps1 in observed fresh runtime. Ventilation scaling commissioning note from prior guide still applies; no calibration/scaling writes.

HIGHWAY-21-GUIDE.md

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+# Highway 21 site guide
+
+Verified October 26, 2026 (America/Edmonton). Production target: https://www.atomhmi.com/site_highway_21/page_well_14. Site ID highway_21; device selector Water. This session inspected configuration only; no alarms, registers, polling, PLC values or pages were saved.
+
+## Program mapping confirmed by user
+
+| Program ID | Well |
+| --- | --- |
+| 0 | Well 5 |
+| 1 | Well 15 |
+| 2 | Well 16 |
+| 3 | Well 4 |
+| 4 | Well 7 |
+| 5 | Well 8 |
+| 6 | Well 9 |
+| 7 | Well 12 |
+| 8 | Well 13 |
+| 9 | Well 14 |
+| 10 | Well 18 |
+| 11 | Well 19 |
+| 12 | Spare |
+| 13 | Spare |
+| 14 | Spare |
+
+## Verified register and alarm catalog
+
+Water has 2,766 register definitions. Search card returns zero matches in the ID/description table. Search unlatched returns 170 entries; search fault returns 60 VFD entries. Existing families include GVL_Well[n]_out_flow_flt_chan_unlatched, GVL_Well[n]_out_lvl_flt_chan_unlatched and GVL_Well[n]_out_vfd_Fault_unlatched, for program indices 0–14. Do not equate these with the requested fault.card.unlatched without confirmation.
+
+Opened GVL_Well[0]_out_flow_flt_chan_unlatched: slave Water PLC; address {"tag":"Application.GVL.Well[0].out.flow.flt.chan.unlatched"}; On Change, one second, Enabled unchecked. Many other unlatched entries are disabled. Definition presence does not establish live readings.
+
+Water has 26 HMI alarm definitions: 12 well low-flow, 12 well low-level, and cistern high/low-level. Existing well entries for index 10 say Well 19 and index 11 say Well 18, opposite the user's mapping. This discrepancy was observed and left unchanged pending scope resolution.
+
+## Requested card fault alarms pending source clarification
+
+User requests all fault.card.unlatched alarms with clear descriptions. No card-named register was found. Clarification requested: new PLC tags requiring import versus existing flow/level channel fault outputs. Do not invent tag paths, register IDs or physical fault meanings. After confirmation, inspect exact sources, add missing definitions with equipment-specific descriptions and quoted Message/Return to Normal expressions, verify persistence, and update this guide.
+
+## Target page observations
+
+Well 14 has flow in gpm, water level in ft, totals in gal, time displays, level/flow trends, and low-flow/low-level enable, threshold and delay controls. Read-only snapshot: 0.0 gpm, water level 8.7 ft. No runtime controls operated. Existing alarm create form supports calculation, importance, latching, on/off delays, notification groups and enabled state; opening a draft was inspection only.

PROJECT.md

@@ -84,3 +84,7 @@ Cloud guide: https://chatgpt.com/space/page_31b800d9541c8191b7eddf6ee2fac319
 ## Arco Poultry — October 22, 2026
 
 ARCO-POULTRY-GUIDE.md documents production site_arco_poultry/page_barn_4. All 22 used registers on barn_controller / slave barn_3_4 (UI label Barn 3) are enabled with one-second ON_CHANGE polling after enabling eight disabled entries. Fresh readback and runtime verification completed; inlet/feed/age readings populated. Temp 1 remains -999 °C and pressure chart label units differ from its axis/numeric display; causes unresolved. Scope is Barn 4 only. Cloud guide: https://chatgpt.com/space/page_3952221801fc8191a490c36a1be0c0c5.
+
+## Highway 21 — October 26, 2026
+
+Production site_highway_21 has a new HIGHWAY-21-GUIDE.md and cloud guide https://chatgpt.com/space/page_068c2a277110819180a2c5853c714e99. User program-to-well mapping recorded. Requested card-fault alarm additions await exact-source clarification; current register catalog has no card-named entries. See guide for verified counts and existing Well18/19 description discrepancy.

cloud-knowledge-base.json

@@ -10,6 +10,7 @@
     "LONE-PINE-GUIDE.md": "page_814209734aa88191bede6b68a663098e",
     "SWEET-GRASS-GUIDE.md": "page_c260b18f6fc08191b2f64da8e5b97182",
     "GLADACRES-GUIDE.md": "page_31b800d9541c8191b7eddf6ee2fac319",
-    "ARCO-POULTRY-GUIDE.md": "page_3952221801fc8191a490c36a1be0c0c5"
+    "ARCO-POULTRY-GUIDE.md": "page_3952221801fc8191a490c36a1be0c0c5",
+    "HIGHWAY-21-GUIDE.md": "page_068c2a277110819180a2c5853c714e99"
   }
 }