audit(specify): repair trailing brainstorm->specify doc drift

Follow-up to f775881. The architect's diff-scoped review missed four
prose references outside the cycle diff that the brainstorm shrink left
stale — the aspirational-marker and parse-gate machinery moved to specify
(it writes the spec and runs the gates), but these still said brainstorm:

- profile-schema.md aspirational-source section: "a later brainstorm
  tell aspirational content", "the brainstorm degrades", "consumed by
  the brainstorm skill", and the "Step-7 parse-every-block gate" number
  (specify's parse gate is Step 4, not Step 7).
- profile-schema.md spec_validation section: "The brainstorm parse-gate".
- README "Retrofitting spec_validation": "brainstorm Step 7 self-review"
  -> "specify Step 4 self-review".

Found by sweeping every brainstorm reference in the two files for ones
that describe spec-production rather than discovery. planner Step 5
self-review and the grounding-check pass references were already correct.

README.md

@@ -117,7 +117,7 @@ the tool that validates a spec code block of that kind. It powers
 the parse gates that stop a spec from shipping code blocks that do
 not parse against the live tool:
 
-- `brainstorm` Step 7 self-review — the parse-every-block gate
+- `specify` Step 4 self-review — the parse-every-block gate
 - `planner` Step 5 self-review — the parse-the-bytes-you-inline gate
 - the `grounding-check` agent's code-block parse pass
 

docs/profile-schema.md

@@ -29,7 +29,7 @@ skip the corresponding step.
 Files under `design_models` (or an equivalent `RFCs` /
 `proposals` directory) commonly carry aspirational code —
 constructs written before the surface that would parse them
-exists. To let a later brainstorm tell aspirational content from
+exists. To let a later specify tell aspirational content from
 validated contract, projects are encouraged (not required) to
 give each such file a frontmatter marker:
 
@@ -49,10 +49,10 @@ reading agent can mechanically tell which carry verified
 behaviour.
 
 When a file lacks the marker the signal is simply absent — the
-brainstorm degrades to treating its content as unmarked, never
-hard-failing. The marker is consumed by the brainstorm skill (see
+specify skill degrades to treating its content as unmarked, never
+hard-failing. The marker is consumed by the specify skill (see
 its Step 1 and Step 4): content lifted from an aspirational source
-is flagged and must clear the Step-7 parse-every-block gate before
+is flagged and must clear the Step-4 parse-every-block gate before
 it ships in a spec.
 
 ## `naming`
@@ -86,7 +86,7 @@ take the next-higher number; deleted files retire their number.
 ## `spec_validation`
 
 Optional. A registry mapping each markdown fence label to the tool
-that validates a spec code block of that kind. The brainstorm
+that validates a spec code block of that kind. The specify
 parse-gate and the grounding-check code-block pass run these
 parsers so that spec code blocks are treated as hypotheses to
 verify, not as authoritative truth.