* chore(#2932): emit a per-invocation section manifest from init
Extends the init bundle with a typed per-invocation section manifest so an
invocation loads only the branch guidance it will actually take.
The three flag/state-gated branches in execute-phase.md move into their own
step files; the parent keeps its gsd:section markers wrapping a one-line
on-demand reference, so each section's prose lives in exactly one file and
the parent shrinks 93369 -> 89507 bytes. A new drift-guarded generator
derives the shipped section manifest from those markers, and a new pure
evaluator maps invocation facts to applicable section ids.
The evaluator is a lookup over the frozen WHEN_VOCABULARY, never a parser
(Greenspun's Tenth Rule, ADR-1671:69); a parity test asserts the vocabulary
and the predicate map stay exhaustively in sync.
Closes#2932
* fix(#2932): fail closed on prototype-chain when values
An isolated adversarial review found WHEN_PREDICATES[section.when] was a
bracket lookup on a plain-prototype object, so inherited Object.prototype
members resolved as predicates: "constructor"/"toString"/"valueOf"/
"hasOwnProperty" returned truthy and SILENTLY INCLUDED the section, and
"__proto__" threw an untyped TypeError carrying no .reason. Both violate
the module's documented fail-closed contract, and the manifest is read from
disk at run time so it cannot be assumed trustworthy.
Builds the predicate map on a null prototype and guards the lookup with an
explicit Object.hasOwn check. Adds table-driven coverage for nine
Object.prototype-shaped keys asserting the TYPED reason (asserting only
that it throws would still pass while broken) plus a fast-check property
injecting a hostile value at an arbitrary document position.
* test(#2932): retarget execute-phase step assertions at extracted step files
* fix(#2932): emit typed reasons for generator lib-load and write failures
* fix(#2932): restore launcher preamble in extracted steps and refresh derived fixtures
* chore(#2932): backfill changeset pr number to 2987
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Co-authored-by: sim <sim@local>
a987cf2731