docs(plan): close ordering question, pin the untested age premise

Two corrections to the brief committed in 3086e8b.

The ordering question (§7.4) still pointed at STATE.md for a decision the
operator had already made, and STATE.md is gitignored — so the tracked artifact
carried a stale queue and deferred to a file a future session cannot read. It
now records the decision inline: delete-and-rebuild goes ahead of pipeline step
4, prior order stands underneath.

§8 gains the premise the brief was quietly resting on: §5A claims project-level
CLAUDE.md/rules yield usable per-block git ages. That is untested. If instruction
blocks trace to one bulk commit, the age signal carries no information and shape
A collapses to the phrasing heuristic — which would answer §7.2 for us. Checked
before any scanner code, not after.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01JNrtHo9hKSLKNyMS6b4Zuy

docs/delete-and-rebuild-brief.md

@@ -130,8 +130,11 @@ workflow that consumes A's output. C stays a documented idea until A+B exist.
    agent layer (like `optimize`'s precision-gated `optimization-lens-agent`)?
 3. Does this ship as its own command, or as a `--subtract` mode of `optimize`?
    Both are defensible; command count is already 21.
-4. Ordering against the existing queue: pipeline step 4 `rollback`, then the
-   M-11→M-20 batch release, then the v5.13 plan. See STATE.md.
+4. ~~Ordering against the existing queue.~~ **Decided 2026-07-29:** the operator
+   prioritized this work ahead of pipeline step 4 (`rollback`), to start Thursday
+   2026-07-30. Do not re-litigate. The open part is only what follows it — the
+   prior order stands underneath: step 4 `rollback`, then the M-11→M-20 batch
+   release, then the v5.13 plan.
 
 ## 8. Verifisering (testable criteria)
 
@@ -143,6 +146,13 @@ workflow that consumes A's output. C stays a documented idea until A+B exist.
       `lib/baseline.mjs` round-trips → confirms §4 reuse is real, not assumed.
 - [ ] If any claim from §1 is to be written into the register: a primary source exists
       (URL to the talk or an Anthropic doc). Otherwise the entry is not written.
+- [ ] **The age signal actually exists.** §5A's fallback claim — "project-level
+      CLAUDE.md/rules get real git ages" — is untested. Run
+      `git log --format=%ad --follow -- CLAUDE.md .claude/rules/` across two or three
+      real repos. If most instruction blocks trace back to a single bulk commit, per-block
+      age carries no information, shape A's primary signal collapses to the
+      compensatory-phrasing heuristic alone, and §7.2 (agent layer) is answered for us.
+      Check this *before* writing any scanner code.
 
 **If shape A is built:**