Reconcile the docs after the last three corrections

The last three commits changed things the documentation still asserted in the
old direction. Fixed:

roadmap
  * 227 tests -> 238.
  * The level_overlay bullet contradicted itself: it said "the header words are
    not named" in the same breath as "+0x00 load base is 0x1A7C80". Now says
    +0x00 IS the load base and is named, +0x0c is excluded as the .lit size by
    sign (below file length on 16/27, by up to 8.9%) and remains unnamed, and the
    unnamed remainder is stated as such.
  * Section names aligned with the Phase 3 list (lvl.vtbl, lvl.camvtbl,
    lvl.sndvtbl).

core-data-regions.md
  * The claim-assertion audit still said the two PCSX2 claims were "NOT
    assertable here -- needs a savestate". They are asserted now, gated on
    GC_SSTATE, in the same file. Updated, with the two corrections that fell out
    of writing them recorded right there.
  * "that string is inside the collision routine" was never established. It is
    in the string pool, yes; the reference to it is not found. Reworded to say
    so, including the zero-hit result.

research log
  * field_00 now carries its name and the .lit/$gp/program context.
  * The field_0c falsification and the byte-order retraction are both recorded
    here as well, so the log and the format file agree.

Nothing left asserting the withdrawn anchor, and no stale test counts.

docs/roadmap.md

@@ -25,7 +25,7 @@ early, while they are still cheap to retire.
       `core_index` class tables, `tfrag` (format, topology, textures, LOD,
       normals, colour), `occlusion`, `sky`, `moby`, `collision` framing and
       header, `shrub` (blob, packets, palette, billboard), the post-shrub
-      `chunks` container, `sound_bank` framing and `level_overlay`. 227 tests
+      `chunks` container, `sound_bank` framing and `level_overlay`. 238 tests
       green against the real disc. **What is open is naming, not locating** --
       see the Phase 2 list for the four types that still have no decoded
       fields: `tie` vertices, collision cells, `SBlk` records, `volumes` and
@@ -399,11 +399,14 @@ Phase 1 hands over the extents; this phase works out what each one contains.
       length, falling below it on 17 levels and above on 10. The debug string
       pool it opens with carries `Camera_CollPrimTest WARNING! - grid out of
       bounds! (RAR)`, independent support for reading the collision payload's
-      two leading `u16`s as grid dimensions. **The header words are not named
-      and the level-specific tail is not structured yet**; the Phase 3
-      seven-section parser and relocation are untouched. The seven sections are
-      now named (`.lit .bss .data vtbl camvtbl sndvtbl .text`) and `overlay.bin`
-      is the `.lit` section, whose `+0x00` load base is `0x1A7C80`.
+      two leading `u16`s as grid dimensions. `+0x00` **is** the load base of
+      the section this file is, `0x1A7C80`, constant on all 27 levels because
+      every level's `.lit` loads there. `+0x0c` is **not** the `.lit` size -- it
+      falls *below* the file length on 16 of 27 levels, by up to 8.9%, so it is
+      excluded by sign -- and it is still unnamed. **The remaining header words
+      are unnamed and the level-specific tail is not structured yet**; the
+      Phase 3 seven-section parser and relocation are untouched, though the
+      seven sections are now named (`lvl.vtbl`, `lvl.camvtbl`, `lvl.sndvtbl`).
 - [x] **The post-shrub chunk container.** A 16-byte header, a 10-byte zero gap,
       then offsets tagged `0xF0000000 | low24` resolving to `chunk_start + low`;
       header byte 14 is the record count, equal to `offsets.len()` on 1,123 of