OPT-09: the weights parameter nothing ever passed, and what it cannot do

`allocator.plan()` has taken a `weights` argument since ALLOC-01 and NOTHING
had ever passed one - main.py called `resolve()` without it and the arbiter
defaulted it to 1.0 per unit - so the site target was split 50/50 regardless
of what either pack could do. Two things now feed it, and they are different
kinds of thing:

  * a `pack` UNIT claim at P_SAFETY that CLOSES a unit's envelope at its own
    `bms_soc_floor` or at 100 % - a PERMISSION, obeyed absolutely, so an empty
    pack is not asked to discharge and its share goes to the sibling;
  * SoC-aware weights by ENERGY headroom in kWh - a PREFERENCE, which
    `_fill()`'s last-resort pass will override the moment the sibling saturates.

Measured (test_packshare.py part 8): at a load one pack cannot cover, the
weighted arm and the shipped arm command the IDENTICAL watts into an empty pack
and deliver the IDENTICAL watts. Only the envelope stops the ask, and what it
buys is not delivery - it is a reported `unmet_w` where the record used to read
impeccable. Weights are a comfort choice for STABILITY and NOT for DELIVERY.

Also: an optional per-entry `capacity_kwh` (schema change, all-or-nothing across
the roster, rule 9 refuses a partial one); per-pack arbitrage sizing, with the
sell side's no-op stated rather than hidden; and a 0 W trade refused by name,
because a 0 W arbitrage claim is a park order that outranks the loop.

SAFETY-42 and this card meet at one hazard from opposite sides - OPT-09 stops
the site ASKING a pack whose SoC says it cannot deliver, SAFETY-42 alarms when a
pack that said it could does not - and its end-to-end fixture moved as a result.
Its finding is unchanged and is now stated on the two quantities its rejected
discriminator actually reads.

Not filed at all at a roster of one: at N=1 every source routes to the site, so
the interval would bound the SITE TARGET, and SAFETY-25's decided Option A
stands untouched on the live install.

⚠️ INVERTER B DOES NOT EXIST. Its 4600 W / 20.48 kWh / 10 % are FROM DATASHEET
AND SERIAL, and `sim/plantsim.py`'s INVERTER_B is inverter A copied
(`measured=False`), so every two-inverter figure here is arithmetic or two
copies of A. No hardware was touched.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BwRLw7eKYj2byVdwB6kbjU

goodwe_controller/test_arbiter.py

@@ -149,7 +149,7 @@ check("...and `source` is still the first positional argument, which is what "
       Claim.limit("device", P_SAFETY, -1, 1).source == "device")
 
 print()
-print("ARB-03 2. the split: eight sources, each classified where it is BUILT")
+print("ARB-03 2. the split: eleven sources, each classified where it is BUILT")
 # The classification is graded against what each claim is ABOUT, restated here
 # so that the table in arbiter.py and the expectation in a test are not the same
 # sentence read twice. test_peakguard.py part 10f pins this set against main.py's
@@ -180,16 +180,25 @@ UNIT_SOURCES = {
                   "measured power (0x0518), so what it learns is about one "
                   "device. The site-wide half moved to `sign_site`",
     "maintenance": "the monthly recalibration is a pack procedure",
+    # OPT-09, and it is the entry a reader will want to check against
+    # SAFETY-25's deferred loop-side reserve, because it has the same shape.
+    "pack":       "THIS pack's own state of charge against THIS pack's own "
+                  "`bms_soc_floor` - a fact about one battery in one cupboard, "
+                  "exactly as `device`'s rating is a fact about one box. It is "
+                  "not SAFETY-25's deferred `loop_soc_floor` reserve: no option "
+                  "is added, `peak_soc_floor` is not consulted, the SITE target "
+                  "is untouched, and main.py does not file it at all at a "
+                  "roster of one",
 }
 for _src, _why in sorted(SITE_SOURCES.items()):
     print(f"    site  {_src:<11} {_why}")
 for _src, _why in sorted(UNIT_SOURCES.items()):
     print(f"    unit  {_src:<11} {_why}")
-check("all TEN claim sources are classified, and only those ten",
+check("all ELEVEN claim sources are classified, and only those eleven",
       set(CLAIM_SCOPE) == set(SITE_SOURCES) | set(UNIT_SOURCES))
 check("the six that are about the GRID CONNECTION are site claims",
       {s for s, v in CLAIM_SCOPE.items() if v == SCOPE_SITE} == set(SITE_SOURCES))
-check("the four that are about a PACK, a DEVICE or one write are per-inverter",
+check("the five that are about a PACK, a DEVICE or one write are per-inverter",
       {s for s, v in CLAIM_SCOPE.items() if v == SCOPE_UNIT} == set(UNIT_SOURCES))
 check("a source nobody classified cannot be routed at all - actuator_for() "
       "raises rather than defaulting to the site, because defaulting to the "
@@ -207,7 +216,7 @@ check("with one inverter every source routes to the site, per-inverter ones "
       all(actuator_for(s, "inverter-a", ONE) == ACTUATOR_SITE for s in CLAIM_SCOPE))
 check("...and with none configured at all, likewise",
       all(actuator_for(s, "inverter-a", ()) == ACTUATOR_SITE for s in CLAIM_SCOPE))
-check("with TWO the identity breaks and the split becomes real: the four "
+check("with TWO the identity breaks and the split becomes real: the five "
       "per-inverter sources route to the unit this controller drives, the six "
       "site sources stay on the grid connection",
       {s: actuator_for(s, "inverter-a", TWO) for s in CLAIM_SCOPE}