fix: DTC 5201 is confirmed, not assumed (MIN 10000TL-X, holding 43)

Marked ASSUMED on the grounds that the maintainer's MIN 10000TL-X
reported no DTC. That was wrong twice over.

I read input register 43 (Iac2, phase 2 current) instead of holding 43,
where the V1.39 DTC actually lives -- the same input/holding mislabelling
in the scanner's Suggested Match column that I had flagged to a reporter
an hour earlier. And the scan I checked was from v0.7.7, which does not
scan the legacy holding range at all, so I treated a range that was never
read as evidence the register was empty.

A v1.1.6 scan on the same unit reads 5201 from holding 43.

Evidence text records that this unit has no VPP range, so the V2.01 key
is downgraded to min_7000_10000_tl_x by convert_to_legacy_profile() --
confirmed as the behaviour of both the live path and the scanner.

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

Author: 0xAHA

custom_components/growatt_modbus/auto_detection.py

@@ -562,7 +562,11 @@ class DtcEntry(NamedTuple):
     ),
     5201: DtcEntry(
         'MIN 7-10KTL-X/X2/X2(E)', 'min_7000_10000_tl_x_v201',
-        ASSUMED, 'no device report on this DTC',
+        CONFIRMED, "maintainer's MIN 10000TL-X, scan on v1.1.6 — DTC 5201 read from legacy "
+                   "holding 43. Note this unit has no VPP range (30000/30099 return Illegal "
+                   "Function), so the V2.01 key below is downgraded to min_7000_10000_tl_x "
+                   "by convert_to_legacy_profile(). It is the reference device most fixes "
+                   "are verified against",
     ),
 
     # -- MOD/MID-XH series --

docs/troubleshooting/dtc-debugging.md

@@ -103,7 +103,7 @@ These statuses live in `DTC_REGISTRY` in `auto_detection.py`, which is the singl
 |----------|-------------|---------|--------|
 | 5100 | MIN 2500-6000TL-XH/XH2/XHE/XA | tl_xh_3000_10000_v201 | ✅ Confirmed (#71) |
 | 5200 | MIC 600-3300TL-X/X2/X2(Pro); MIN 2500-6000TL-X/X2/X2(Pro)/X2(Pro.E) | min_3000_6000_tl_x_v201 | ⚠️ Unconfirmed — refined at runtime by per-MPPT energy check |
-| 5201 | MIN 7-10KTL-X/X2/X2(E) | min_7000_10000_tl_x_v201 | ⚠️ Unconfirmed |
+| 5201 | MIN 7-10KTL-X/X2/X2(E) | min_7000_10000_tl_x_v201 | ✅ Confirmed (MIN 10000TL-X, DTC from legacy holding 43) |
 
 ### MOD / MID / MAC Series — Three-Phase Hybrid / Grid-Tied