Switch lamps to internal IDs; EAN becomes optional metadata

Directories rename from bare EANs to L0001..L0010 (measurement order).
metrics.json gains an ean field, and a rated block with advertised
values (flux, CCT, power, lifetime) where already documented, so the
site can show advertised-vs-measured deltas. One EAN can now cover
several lamp versions (variant field) and unbranded lamps need no
barcode.

README.md

@@ -11,16 +11,22 @@ renaming a directory here requires updating the matching page in the web repo.
 ## Layout
 
 ```
-lamps/<EAN>/spd.csv         SPD 380-1050 nm: wavelength_nm,value
-lamps/<EAN>/tm30.csv        ANSI/IES TM-30-18 per-hue-bin data (16 bins): Rcs, Rhs, Rf_h, ...
-lamps/<EAN>/metrics.json    Summary: TM-30 Rf/Rg, CRI Ra + R1-R15, CCT, flux, instrument metadata
+lamps/<ID>/spd.csv          SPD 380-1050 nm: wavelength_nm,value
+lamps/<ID>/tm30.csv         ANSI/IES TM-30-18 per-hue-bin data (16 bins): Rcs, Rhs, Rf_h, ...
+lamps/<ID>/metrics.json     Summary: TM-30 Rf/Rg, CRI Ra + R1-R15, CCT, flux, instrument metadata
 solar-charge-controllers/<device>.csv   Efficiency sweep: set/measured Vin, Iin, Pin, Vout,
                                         Iout, Pout, eff_pct, heatsink and board temperature
 ```
 
-Lamps are identified by their EAN barcode so results stay unambiguous across brands and
-packaging variants. EANs starting with 2 are retailer-internal barcodes that cannot be
-resolved publicly.
+Every lamp has an internal ID (`L0001`, `L0002`, ...) as its primary key, assigned in
+measurement order by `lamp_station.py`. The EAN barcode is optional metadata in
+`metrics.json` (`ean`): one barcode can cover several versions of a lamp (daylight and
+warm white sharing box art get distinct IDs and a `variant` field), unbranded lamps have
+no barcode at all, and EANs starting with 2 are retailer-internal codes that cannot be
+resolved publicly. `metrics.json` may also carry a `rated` block with the advertised
+values from the packaging (`Phi_lm`, `CCT_K`, `Power_W`, `Ra`, `lifetime_h`, `W_equiv`),
+keyed like their measured counterparts so consumers can render
+advertised-vs-measured comparisons.
 
 ## Provenance
 

lamps/L0001/metrics.json

@@ -1,8 +1,16 @@
 {
-  "name": "8718696822708",
+  "name": "L0001",
+  "ean": "8718696822708",
   "manufacturer": "Philips",
   "model": "LEDBulb 8W E27 3000K (68W equivalent, 770 lm)",
   "notes": "",
+  "rated": {
+    "Phi_lm": 770,
+    "CCT_K": 3000,
+    "Power_W": 8,
+    "lifetime_h": 15000,
+    "W_equiv": 68
+  },
   "instrument": "HPCS6500",
   "measured_at": "2026-07-08T12:01:34+07:00",
   "instrument_date": "2026-07-08",