fix: correct the P-row misuse and the basis tier ordering

Both from info-tech-canon's review of the restatement.

STRAIN 1 — credential custody was recorded as one unit of class P consumption.
P is purchased platform capacity, and using security.secrets buys none. Removed
the row; the relationship now sits in provisions[].uses_provisions alongside the
object-store dependency, marked explicitly as a proposed extension because
ITC-CAP declares no provision-to-provision relation. Filed as
info-tech-canon/demand/ProvisionRelationships.md (their commit ce17dc4).

BASIS TIERS — their point about invoiced being a fin-hub fact we name rather
than originate exposed a real bug: a strict list order made weakest(["invoiced",
"measured"]) return "measured", implying an invoice outranks a measurement. It
does not outside its own domain. Strength is now a tier — invoiced and measured
are peers, quoted below both — with ties broken deterministically by catalog
order without implying a difference that does not exist.

Also filed info-tech-canon/demand/EvidenceBasis.md at their request, proposing
ITC-GOV as owner rather than ITC-CAP.

187 tests pass.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

tools/basis.py

@@ -30,31 +30,51 @@ BASIS_ORDER = (
     "unknown",    # no value exists
 )
 BASES = frozenset(BASIS_ORDER)
-_RANK = {name: index for index, name in enumerate(BASIS_ORDER)}
+
+# Strength is a tier, not a total order. `invoiced` and `measured` are peers:
+# an invoice is the authoritative record of a payment, a measurement is the
+# authoritative record of a quantity, and neither outranks the other outside
+# its own domain. Asserting an order between them would make the weakest-input
+# rule claim something it cannot know.
+_TIER = {
+    "invoiced": 0, "measured": 0,
+    "quoted": 1,
+    "derived": 2,
+    "projected": 3,
+    "estimated": 4,
+    "assumed": 5,
+    "unknown": 6,
+}
+_ORDER = {name: index for index, name in enumerate(BASIS_ORDER)}
 
 # Bases that assert an observed or contracted fact about the world.
 EVIDENCED = frozenset({"invoiced", "measured", "quoted"})
 
 
 def rank(basis: str) -> int:
-    if basis not in _RANK:
+    """Strength tier; lower is stronger. Peers share a tier."""
+    if basis not in _TIER:
         raise ValueError(f"unknown evidence basis {basis!r}")
-    return _RANK[basis]
+    return _TIER[basis]
 
 
 def weakest(bases) -> str:
-    """The weakest basis in a collection. Empty means nothing is known."""
+    """The weakest basis in a collection. Empty means nothing is known.
+
+    Ties within a tier resolve by catalog order so the result is deterministic
+    without implying a strength difference that does not exist.
+    """
     bases = list(bases)
     if not bases:
         return "unknown"
-    return max(bases, key=rank)
+    return min(bases, key=lambda b: (-rank(b), _ORDER[b]))
 
 
 def strongest(bases) -> str:
     bases = list(bases)
     if not bases:
         return "unknown"
-    return min(bases, key=rank)
+    return min(bases, key=lambda b: (rank(b), _ORDER[b]))
 
 
 def is_evidenced(basis: str) -> bool: