monorepo: one repository for the decoders, the port and the corpus

Merges the Godot port into the reverse-engineering repository, preserving both
histories -- 1019 commits of corpus plus the port's 31, brought in by subtree
merge and then moved into place so git can follow each file across the rename.

The reason is not tidiness. The two-repo split forced the exporter to depend on
the decoders by pinned revision, and that created a whole class of failure that
now disappears: a sha reachable only from a topic branch, orphaned by a
squash-merge, breaking a fresh checkout silently at build time. It also forced a
live read-only mount of one agent's working tree into another's container, which
is why a contract file could move mid-iteration. With a path dependency, a
decoder change and the exporter change it requires land in the same commit or
not at all.

Canary stays separate: it is a fork tracking upstream.

New structure for the long term:

  docs/game/     how the game is NAVIGATED -- menus, modals, prompts, alerts,
                 and in-game flight. Written so nobody rediscovers it. Mostly
                 open questions on purpose; the in-game tutorials are the
                 resource for the flight half.
  docs/port/MODDING.md
                 modding as a constraint on the exporter TODAY, not a later
                 feature: one logical asset in one file (the disc splits nearly
                 everything, and resolving that is the exporter's job), names a
                 person recognises, PNG/OGG/OGV/JSON only, base-and-overrides so
                 re-exporting is always safe, provenance in every file.
  data/base + data/mods
                 generated tree and drop-in overrides, both gitignored
  exchange/      transient inter-agent files, deliberately outside history
  docs/agents/   the team protocol

Both the README and the navigation doc lead with the correction that cost the
most: the oracle is the real game under Xenia Canary. Reborn's renderer is a
hypothesis under test, it has been wrong, and treating it as ground truth
propagated into three documents and both agents before a human caught it.

Scripted modding stays possible without being built: no screen name is hardcoded
in GDScript and there is no native code in port/, which is what Godot Mod Loader
needs to be able to substitute behaviour later.

authored/screen_names.json

@@ -0,0 +1,94 @@
+{
+  "format": "sylpheed.screen_names/1",
+  "_": [
+    "Which GP_TITLE pak entry is which screen. AUTHORED: the disc does not name its",
+    "builds, so every name here is a decision. The identifications come from",
+    "HANDOFF Q2 (ui-title-build-map.md), which measured them against framebuffer",
+    "captures of the running game; the exporter stamps the name into the screen",
+    "file with name_source: \"authored\" so a reader can tell a recovered name from",
+    "an invented one.",
+    "",
+    "KEYED BY PAK ENTRY INDEX, not by the enumeration ordinal. It used to be the",
+    "ordinal; widening the enumeration to reach the splash renumbers ordinals, and",
+    "a name that moves when the enumeration rule changes is not a name. The entry",
+    "was always described here as the stronger locator -- now it is the only",
+    "stable one.",
+    "",
+    "Delete an entry here the day the RE agent decodes a name field."
+  ],
+  "archives": {
+    "dat/GP_TITLE.pak": {
+      "2": {
+        "name": "press_start",
+        "why": "HANDOFF Q2: builds 2/3 are the PRESS (A) BUTTON plate -- a build of its own, composited over the title and faded in a beat later. English of the EN/JP pair. Measured against a live capture."
+      },
+      "3": {
+        "name": "press_start_jp",
+        "why": "HANDOFF Q2: the Japanese twin of build 2. Out of scope for this milestone; named so it is not mistaken for a screen we need."
+      },
+      "4": {
+        "name": "title",
+        "why": "HANDOFF Q2: build 4 is the English title art. Measured against a live capture."
+      },
+      "5": {
+        "name": "main_menu",
+        "why": "HANDOFF Q2: builds 5/8 are the five-button main menu; 5 is English. Measured against a live capture. (An earlier reading called 8 a submenu and was withdrawn -- 8 is the Japanese main menu.)"
+      },
+      "6": {
+        "name": "extras",
+        "why": "HANDOFF Q2: builds 6/9 are the EXTRAS submenu, the only submenu inside this archive. Measured against a fresh EXTRAS capture."
+      },
+      "7": {
+        "name": "title_jp",
+        "why": "HANDOFF Q2: the Japanese twin of build 4."
+      },
+      "8": {
+        "name": "main_menu_jp",
+        "why": "HANDOFF Q2: the Japanese twin of build 5."
+      },
+      "9": {
+        "name": "extras_jp",
+        "why": "HANDOFF Q2: the Japanese twin of build 6."
+      },
+      "10": {
+        "name": "publisher_logo",
+        "why": "The SQUARE ENIX PUBLISHER wordmark -- the FIRST thing the boot sequence shows, before the developer logos. Measured by the RE agent 2026-08-29, render grid at docs/re/captures/title-builds/splash-both-halves-rendered.png. Entries 10/13 are region twins distinguished by the trademark glyph; 10 carries the (TM)."
+      },
+      "13": {
+        "name": "publisher_logo_r",
+        "why": "The region twin of entry 10, carrying (R) where 10 carries (TM). Named so it is not mistaken for a second screen the boot path needs."
+      },
+      "11": {
+        "name": "developer_logos",
+        "why": "The GAME ARTS / SETA / studio anima logos -- the developer splash, shown after the publisher wordmark. HANDOFF Q2 and the RE agent's 2026-08-29 render grid; draws 7/7 elements."
+      },
+      "14": {
+        "name": "developer_logos_r",
+        "why": "The region twin of entry 11, as 13 is to 10."
+      }
+    }
+  },
+  "unnamed": {
+    "dat/GP_TITLE.pak": "Entries 0/1 and 12/15 are plates never seen running -- not in the boot path, not on any title-side screen, not in the attract loop (HANDOFF Q2). They export under their entry index rather than a name we would be inventing."
+  },
+  "also_export": {
+    "dat/GP_TITLE.pak": {
+      "10": {
+        "name": "publisher_logo",
+        "why": "LOCATED BY ENTRY INDEX, not by a rule. These four bundles declare their sprites directly and have no .rat layout child, so `is_build` cannot see them -- and the RE agent established that NO content rule can: design size fails (every extra composable bundle sampled is 1280x720, the same as every screen) and element count fails (fragments run 2..15 elements in GP_OPTIONS/GP_SAVE_LOAD while these are 3 and 7 -- the ranges overlap). Safe here and not in general: in GP_TITLE the widened set adds exactly these four and all four are real screens, zero fragments."
+      },
+      "11": {
+        "name": "developer_logos",
+        "why": "As entry 10: located by index because no content rule distinguishes a splash from a fragment. 7 elements, all drawn."
+      },
+      "13": {
+        "name": "publisher_logo_r",
+        "why": "As entry 10, region twin."
+      },
+      "14": {
+        "name": "developer_logos_r",
+        "why": "As entry 11, region twin."
+      }
+    }
+  }
+}