DOC-1: operator docs name the real P1 entity and a roster that starts

- DOCS.md / config.yaml: the watchdog's P1 age entity is
  sensor.goodwe_p1_sample_age (device "GoodWe" + "P1 sample age", as
  app/mqtt.py announces and the live install recorded), not
  sensor.p1_sample_age_s.
- DOCS.md: the inverters: example and per-entry table carry the required
  bms_soc_floor (and capacity_kwh); config.yaml's schema comment says four
  required keys, not three.
- Field guide: marked v0.1.0/outdated; slew_w row no longer recommends the
  1000 W that SAFETY-39 now refuses. HTML regenerated; the PDF is NOT
  rebuilt (no Chrome here). README/DOCS pointers fixed.
- test_docs.py: the documented roster must pass app/validate.py and the
  schema's per-entry keys; the documented entity id must equal the id
  composed from app/mqtt.py; the wrong id may appear in no shipped doc.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwRLw7eKYj2byVdwB6kbjU

README.md

@@ -30,7 +30,7 @@ goodwe_controller/         the add-on
                            returns, run against its own release image
 firmware/goodwe-master.yaml  ESPHome config for the T-CAN485
 estop/rs485_log.py           optional RS485 e-stop / bus witness
-docs/GoodWe-RS485-Field-Guide.pdf  the guide techs carry (10pp, A4)
+docs/GoodWe-RS485-Field-Guide.pdf  the guide techs carry (10pp, A4; outdated)
 docs/build_guide.py          its single source - rebuilds the HTML and PDF
 FIELD-GUIDE.md             how to edit and rebuild the guide
 docs/RELEASE.md            how a change reaches the battery - `master` is
@@ -79,8 +79,8 @@ machine itself dying:
 2. **Wind-down before firmware updates** — 0 W written before the update starts.
 3. **RS485 e-stop (optional)** — writes 0 W after 30 s of total bus silence.
 
-Sites sold without the e-stop must have the acknowledgement in `FIELD-GUIDE.md`
-§10 signed.
+Sites sold without the e-stop must have the client acknowledgement in the field
+guide (Step 7b) signed.
 
 ## Development