docs(ledger, glossary, guide): construction args across the surfaces

C24 gains the add-op args clause and the data-driven format-version
paragraph (tier-2 discipline with id-stability); C15's current state
records Session as args-authorable; the glossary defines construction
arg and arg kind (and de-stales the session-node entry to aura-market);
the authoring guide fixes the moved roster path, extends the
Session-anchoring section with the args path, and teaches the add-op
args row; the README op-list sentence notes args on arg-bearing types.

refs #271

docs/design/contracts/c24-blueprint-data.md

@@ -197,10 +197,17 @@ replayed in order; nodes are referenced **by identifier**, ports as dotted
   from the slots it feeds) — a reusable **pattern**'s formal parameter, left open
   until an enclosing graph wires it (#317's open patterns): `finish()` accepts an
   op-script that never binds it, only `compile`/bootstrap require it bound.
-- `add` — `{"op":"add","type":<TypeId>,"name":<str>?,"bind":{<param>:<Scalar>}?}` —
+- `add` — `{"op":"add","type":<TypeId>,"name":<str>?,"args":{<arg>:<str>}?,"bind":{<param>:<Scalar>}?}` —
   add a node of compiled-in type identity `type`; **`name` is its identifier**
   (mirrors the builder's `.named(...)`; defaults to the lowercased type label, so
-  two unnamed nodes of one type collide); `bind` sets params.
+  two unnamed nodes of one type collide); `args` (#271) configures an **arg-bearing**
+  type's structural, non-scalar construction (`Session`'s IANA timezone/open,
+  `LinComb`/`CostSum`'s arity) through the closed, load-time-validated `ArgKind`
+  table (`Tz`/`TimeOfDay`/`Count`) — applied BEFORE `bind`, so a bound param
+  `args` unlocks (e.g. `LinComb`'s `weights[i]`) is only bindable once `arity` is
+  consumed; an arg-bearing type given no `args` refuses (`BadArg(MissingArg)`), a
+  `Plain` type given `args` it does not declare also refuses
+  (`BadArg(NotArgBearing)`); `bind` sets the (now real) params.
 - `feed` — `{"op":"feed","role":<str>,"into":[<port>,…]}` — fan a root role into
   interior input slots.
 - `connect` — `{"op":"connect","from":<port>,"to":<port>}` — wire an interior output
@@ -269,6 +276,14 @@ additive-optional fields of v1; the first ship consciously freezes v1, gangs inc
 and activates the bump discipline. The per-section required-flag scheme is deferred (no
 current Tier-2 section to validate it; recorded on #156).
 
+**First data-driven bump (#271):** construction args are the first Tier-2 case whose
+version is decided PER DOCUMENT, not a single global bump. The writer emits
+`format_version: 1` for an args-free document (byte-identical to every pre-#271
+document — content ids stable) and `2` the moment any primitive, at any composite
+nesting depth, carries `args` — the must-understand signal an old (pre-#271) reader
+needs, since it cannot construct a pending arg-bearing type at all. The loader accepts
+the closed range `1..=2`.
+
 ### Enforcement shift — invariant 9 on the data plane
 
 Lifting topology onto the data plane relocates *where* the engine/project boundary