Add results-file spec: the AI -> Business handover columns

Corrected and extended from the RL Evaluation seat's spreadsheet draft:
snake_case names with units, controller as a column value, identity and
version columns, the energy totals Business's register rows need, and the
open questions for Business. S0 (no hydrogen) is a Simulations scenario, not
a controller.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

docs/02-specifications/simulator-io-interface.md

@@ -93,7 +93,7 @@ Set once per simulation run.
 |---|---|---|---|
 | `N_c_ele` | Number of cells | — | Usually difficult to find |
 | `mu_F` | Faraday efficiency | — | Fall back to literature average (~0.95–0.99 for PEM) |
-| `P_Electro_max` | Rated / max power | W | |
+| `P_ele_max` | Rated / max power | W | |
 | `P_ele_min` | Minimum operating power | W | Below this the electrolyser shuts off (efficiency cliff) |
 | `I_ele_min` | Minimum operating current | A | Alternative to `P_ele_min` |
 | `cal_H2` | H₂ production calibration factor | — | If we end up reading H₂ flow from measured data |
@@ -104,14 +104,13 @@ Set once per simulation run.
 |---|---|---|---|
 | `N_c_fc` | Number of cells | — | |
 | `utilisation_fc` | H₂ utilisation | % | |
-| `P_FuelCell_max` | Maximum output power | W | **Project spec: 100 kW** |
+| `P_fc_max` | Maximum output power | W | **Project spec: 100 kW** |
 | `V_fc_min`, `V_fc_max` | Operating voltage range | V | |
 
 ### 1.3 Hydrogen tank
 
 | Symbol | Name | Unit | Notes |
 |---|---|---|---|
-| `E_H2_max` | Maximum electrical energy capacity of the storage tank | J | |
 | `V_H2_max` | Maximum stored volume | L (or kg) | **Project spec: up to 200 kg total across two tanks** |
 | `V_H2_init` | Initial fill level | L (or kg) | |
 | `T_tank` | Operating temperature | K | TBD — isothermal assumption likely fine |
@@ -130,11 +129,9 @@ Set once per simulation run.
 | Symbol | Name | Unit | Notes |
 |---|---|---|---|
 | `E_rated` | Rated energy capacity | Wh | |
-| `E_battery_max` | Maximum energy capacity | Wh | |
 | `Q_rated` | Rated charge capacity | Ah | |
-| `P_battery_max` | Max (dis)charge power (assuming both are identical - this is the current assumption in the Simulink Controller) | W | |
-| `P_battery_charge_max` | Max charge power | W | |
-| `P_battery_discharge_max` | Max discharge power | W | |
+| `P_batt_charge_max` | Max charge power | W | |
+| `P_batt_discharge_max` | Max discharge power | W | |
 | `SoC_init` | Initial state of charge | — (0–1) | |
 | `SoC_min`, `SoC_max` | Operating window | — (0–1) | E.g. 0.1–0.9 |
 | `eta_batt_ch`, `eta_batt_dis` | Round-trip efficiencies | — | Often split into charge & discharge |
@@ -198,8 +195,6 @@ Carried forward to the next step.
 | Symbol | Name | Unit |
 |---|---|---|
 | `SoC(t)` | Battery state of charge | — (0–1) |
-| `E_battery_SOC(t)` | Energy currently present in battery | J |
-| `E_H2_SOC(t)` | Electrical Energy that can be currently extracted from the Hydrogen Storage Tank | J |
 | `H2_level(t)` | H₂ stored in tank | mol (or kg) |
 | `T_tank(t)` | Tank temperature | K (only if non-isothermal model) |
 | `p_tank(t)` | Tank pressure | bar (if modelled) |
@@ -208,7 +203,7 @@ Carried forward to the next step.
 
 | Symbol | Name | Unit |
 |---|---|---|
-| `P_PV(t)` | PV power available given irradiance | W |
+| `P_PV_available(t)` | PV power available given irradiance | W |
 | `P_PV_used(t)` | PV power actually consumed | W |
 | `P_PV_curtailed(t)` | PV potential that was thrown away | W |
 | `P_ele(t)` | Actual electrolyser consumption | W |
@@ -217,12 +212,6 @@ Carried forward to the next step.
 | `P_grid(t)` | Actual grid flow (signed) | W |
 | `P_load_served_crit(t)` | Critical load served | W |
 | `P_load_served_noncrit(t)` | Non-critical load served | W |
-| `P_load_P(t)` | Power to be covered after PV (+ve = remaining power shortage, -ve = surplus to be used) | W |
-| `P_load_PB(t)` | Power to be covered after PV and Battery (same convention as P_load_P) | W |
-| `P_load_PBH(t)` | Power to be covered after PV, Battery and Hydrogen stroage tank (same convention as P_load_P(B)) | W |
-| `P_battery_cont(t)` | Power amount the controller determines the battery should (dis)charge at (accounting for battery properties and demand) | W |
-| `P_FuelCell_cont(t)` | Power amount the controller determines the fuel cell should provide (accounting for it's properties and demand) | W |
-| `P_Electro_cont(t)` | Power amount the controller determines the electrolyser should extract (accounting for it's properties and demand) | W |
 
 ### 3.3 Mass flows (hydrogen)