D229: fix green/pulsating IsWater water -- fast3d wasn't expanding CI8 indices

texSelect loads the water image as ZLIB+CI8 (raw 8-bit palette indices);
GE's custom RSP ucode expands them to RGBA16 in TMEM at load time, so a
later RGBA/16b tile re-declaration over the same slot samples real blue
pixels. fast3d has no such expansion and read the raw index byte-pairs as
16-bit texels (g dominates -> green mottle); the "pulsing" was always the
pre-existing PRIM_LOD_FRAC sinf() cross-fade between two mis-decoded tiles.

Track each TMEM load's source G_IM_FMT in LoadedTexture.src_fmt; in
import_texture, an RGBA/16b tile over a CI-sourced slot now routes through
the CI8 palette import path instead. Fires only on the genuine format
disagreement, so real RGBA16 textures are untouched.

Verified live on Frigate (-level_26): water renders blue, user confirms
"looks better". Sweep + Surface 2 by-eye still owed.

Also files D245 (water seam), D246 (edge strips), D247 (black bars) from
the same playtest session.

Claude-Session: https://claude.ai/code/session_016DQUKGLZxFtPy52MkKXXog

docs/dev/GE-ENV-PROBES.md

@@ -72,6 +72,7 @@ Two classes:
 | `GE_D85DUMP` | `src/game/bg.c:2510` | D85 `bgWidenRoomGdl` 8→16B dump | dead (D85 closed) |
 | `GE_D85TEX` | `src/game/image.c:2479`, `src/game/tex.c:859,1050` | D85 texpool-full events (Depot analysis) | dead (D85 closed) — was useful for §3 |
 | `GE_D217TEX` | `src/game/image.c:234` (`texInflateZlib`) | D217: logs `texnum`/`format`/`numcolours`/`palette[0..1]` straight off the decode bitstream (before any arena/pointer math) — the decode-correctness check that proved the affected texture (grip, `texnum=1608`) decodes byte-identically across levels, ruling out a decode/ROM-data bug. | **live** (D217 open — investigation instrument) |
+| `GE_D229` | `port/fast3d/gfx_pc.cpp` (`gfx_sp_tri` dual-texunit probe + `import_texture`) | D229: per-draw dump of both texunits' tile/tmem/fmt/siz/UV state for 2-cycle draws, plus a one-shot confirm line when the RGBA16-over-CI8 import remap fires (the fix path). Inert by default. | **live** (D229 fixed — probe kept for the Surface 2 / sweep verification) |
 | `GE_D86` | `src/game/model.c:6295`, `src/game/objecthandler_2.c:143` | D86 model rwdata trace | dead (D86 closed) |
 | `GE_D87` | `src/game/ramromreplay.c:296,363,381` | D87 `ramromfilestructure` endianness | dead (D87 closed) |
 | `GE_D88` | `src/game/prop.c:1367`, `src/game/stan.c:3090` | D88 `Usetup*Z` propDef stream | dead (D88 family closed; D88.4 resolved) |