ci: warn on dev-docs size budgets (ctx-opt P2)

Warn-only (non-fatal): findings.md §F table region > 150 KB means fat rows
are accumulating again (cell content belongs in ## Dxx sections; lookup path
is findings-index.csv); porting-notes.md > 120 KB. Lit until Bucket B of the
ctx-opt migration lands (~266 KB today). HANDOFF.md is gitignored so its
> 30 KB budget stays a local check.

.github/workflows/ci.yml

@@ -138,6 +138,16 @@ jobs:
           python3 tools_pc/gen_findings_index.py --check
           python3 tools_pc/gen_env_probes.py --check
 
+      # Docs budget guardrail (ctx-opt P2): warn, don't fail. The §F index
+      # table should stay one-liners; fat cell content belongs in `## Dxx`
+      # sections at the file tail (lookup path: docs/dev/findings-index.csv).
+      - name: Check dev-docs size budgets (warn only)
+        run: |
+          f=$(awk '/^### F\./{f=1;next} /^### G\./{f=0} f' docs/dev/findings.md | wc -c)
+          [ "$f" -le 153600 ] || echo "WARNING: findings.md §F table region is $f bytes (> 150 KB) — fat rows accumulating; migrate cell content to ## Dxx sections"
+          p=$(wc -c < docs/porting-notes.md)
+          [ "$p" -le 122880 ] || echo "WARNING: porting-notes.md is $p bytes (> 120 KB) — consider splitting or adding a TOC block"
+
       # US only. gen_romassets.py resolves every symbol for the US region from
       # the committed CSVs with no ROM present; PAL/JP each need a handful of
       # region-specific prop/font offsets that only come from that region's ROM