Docs hygiene: enforce in /alignment, add eng-council Documentation seat and beyond-scope notes

.claude/skills/alignment/SKILL.md

@@ -126,9 +126,28 @@ Review all changes in scope. If changes span multiple patterns below, apply all
     apply migrations; destructive actions (delete, revert, reset) confirm; storage failures
     warn rather than silently lose data.
 
-13. **Self-containment**: documentation and comments must not add pointers that require an
-    external repository to follow. Knowledge gets captured locally (`docs/spec/`,
-    `docs/architecture/`), not linked out.
+13. **Documentation hygiene** (the docs are maintained artifacts; keep them at altitude):
+    - **Self-containment**: documentation and comments must not add pointers that require an
+      external repository to follow. Knowledge gets captured locally (`docs/spec/`,
+      `docs/architecture/`), not linked out.
+    - **Matter-of-fact, as rule #6 demands of comments**: docs state _what the design is_ +
+      the standing _why_, never the build narration (`this bit us`, `we chose X over Y`,
+      `resolves the former divergence`, `council resolution recorded`). A decision is recorded
+      by stating its resulting rule, not the story of reaching it.
+    - **No stale-prone constructs** — three things rot the moment the code moves:
+      - **TS code blocks that copy current implementation.** A snippet mirroring a real
+        module goes stale on its next rename. An illustrative _shape_ sketch is fine; a copy
+        of specific current code is a finding — replace it with a navigation map (`file →
+role`) or the rule it demonstrates.
+      - **Positional sub-section cross-refs.** Cite a doc by a stable identifier — the file
+        (`spec §07`, `arch 02`) or a named section / quoted rule — never a positional
+        sub-section number (`arch 07 §4`) that renumbers when a section is inserted above it.
+        Applies to code comments too.
+      - **Volatile exact counts.** Test counts, file/LOC counts, and one-off timings churn
+        daily and read as stale within a week. State the qualitative fact ("seconds of layout
+        on a large dataset"), not the measured number. The only homes for exact figures are
+        `docs/exploration/` records (frozen by definition) and `docs/codebase-metrics.md` (the
+        deliberately-tracked trend).
 
 14. **User-facing copy**: keep user-visible strings centralized and written for users (sentence
     case, active voice, no "please", no exclamation marks in errors). If/when an i18n layer