docs(D185): fresh d69_emit.py run produces a crashing pccg sidecar — alpha blocker

docs/dev/findings.md

@@ -5018,3 +5018,41 @@ golden + a Streets/Dam/Archives load.
 Docs only: this subsection + the §F index rows (D88.4 status, new D132
 row). No code changed; the proposed diff above is not applied. No temp
 probe scripts left.
+
+## D185 — fresh `d69_emit.py` run yields a game-crashing `data/pccg-<region>/` (M-38)
+
+**Status: OPEN — alpha-release blocker.** (Add to the §F index.)
+
+**Symptom.** `python tools_pc/d69_emit.py ntsc-final` in this repo writes
+`data/pccg-ntsc-final/pccg.bin` = 3346895 B (52 sidecars, 1856-B manifest),
+prints `ALL CHECKS PASSED`, and `-level_09` / `-level_20` then segfault before
+frame 1 (`EXCEPTION: 0xc0000005`, faulting return address is an ASCII
+model-name string). The pre-migration working sidecar
+(`C:/Users/james/Source/Repos/007/data/pccg-ntsc-final/pccg.bin`, 3604378 B,
+2421-B manifest) drops into this tree and `-level_09` runs crash-free.
+
+**Isolation done (M-38).**
+- Not the romdata M-38 change: baseline (stashed) crashes identically.
+- Not the build: same exe, only the `data/pccg-ntsc-final/` bytes swapped.
+- `tools_pc/d69_emit.py` is byte-identical between the public repo and the
+  pre-migration repo `007` (only a doc-path comment differs).
+- The migration commit `52539d10 "Prepare for public release"` normalised the
+  committed d69 inputs from CRLF to LF: `scripts/filelist.u.csv` (−812 B, one
+  CR/line) and `assets/obseg/file_resource_table.inc.c`.
+- **Restoring CR to both inputs did NOT restore the 3604378-B output** → line
+  endings are not the (whole) cause. Some other part of the d69 input closure
+  regressed in the history rewrite, or the working sidecar predates a real
+  d69/​input change and 3346895 is a separate second bug.
+- `d43_emit.py` is unaffected (its `find_row` tries `name`, `name[1:]`,
+  `name[:-1]`, `name[1:-1]` — tolerant of a mangled basename; `d69`'s
+  `fl_by_base.get(basename)` is exact).
+
+**Impact.** `docs/building.md` tells users to run `d69_emit.py`; M-38's
+`prepare-assets.py` does the same. Both currently produce a broken game on a
+clean checkout. The committed `data/` dirs (carried from pre-migration) hide it.
+
+**Next.** Diff the sidecar *name* set: pre-migration `manifest.csv` vs a fresh
+run's — find which bg/stan entries d69 now drops, trace through `find_row` →
+`file_resource_table.inc.c` → `filelist.u.csv`. Fix so a fresh run reproduces
+3604378 B / 2421-B manifest; re-verify `-level_09`/`-20` crash-free. Do NOT
+regenerate `data/pccg-ntsc-final/` before the fix (it holds the working copy).