port: the container agent answers the questions, it does not build the port

Corrects the split I got wrong in b5a1938. The container is for reverse
engineering, now focused on the menu port; a SEPARATE agent builds the port from
its investigation results. My previous version had the container agent writing
the exporter and the Godot project, which is not the intent.

This lands on the research/engineering line that was already in the estimate:
the container agent takes the research half, the port agent the engineering half.

docs/port/MISSION.md is now a list of open QUESTIONS (Q1-Q9) rather than build
milestones, ordered by what blocks the port earliest -- the keyframe time unit,
which build is which screen state, paint order for the six screens, button ->
GamePart, navigation semantics, the boot sequence driver, transitions, menu
audio bindings, and video binding. Each is done when a written result with
evidence exists, not when something compiles. S1, the Ready Room probe, stays
gated at one iteration and a go/no-go.

Most of these are BEHAVIOUR questions -- timing, transitions, what a d-pad press
does at the end of a list -- so the mission and the loop prompt both push hard
on measuring the oracle rather than reasoning from the file.

docs/port/FORMAT.md is deleted. The export schema is the port agent's design and
was not mine to specify. It is replaced by docs/port/HANDOFF.md, the single page
the port agent reads: a status table, what is already settled and can be relied
on today, and the facts that will trip the port up (the WMV3/WMA Pro intro, the
Static.slb size over-declaration, the voice-vs-music downmix, JNGL_001).

The derived/authored idea survives as the thing it always was -- a finding, not
a design. Every answer must be classified DECODED, MEASURED or UNDECODABLE-with-
reach, and never a fourth thing, because measured and undecodable both mean the
port agent is authoring that value and has to know it. Labelling a guess as a
decode would put it into the port wearing the badge of a measurement.

Reverts the Godot install from the RE container, its AGENT.md section, and the
export/ gitignore entry -- none of that belongs on this side of the wall.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

docs/port/HANDOFF.md

@@ -0,0 +1,93 @@
+# Handoff — what the menu port needs, and where it stands
+
+The single page the **port agent** reads. Everything here is produced by the
+container agent's reverse engineering; nothing here is a design decision about
+the port itself.
+
+Keep it current. It is a summary with links into `docs/re/`, not a second copy of
+the findings — but an answer that is not reachable from this page has not been
+delivered.
+
+## How to read an answer
+
+Every row below is one of exactly three things, and the distinction is the point:
+
+| | meaning | what the port should do |
+|---|---|---|
+| **decoded** | a field on the disc, with a disc-wide check | read it from the data |
+| **measured** | not on the disc in any form we found, but the running game does *this* | hardcode it, and cite this page |
+| **undecodable** | we looked in these places, it is not there, here is the reach of the negative | author it by hand, knowingly |
+
+There is no fourth kind. If a row says *measured* or *undecodable*, the port is
+**authoring** that value, not transcribing it — and it should be kept somewhere a
+human can see it is a human decision, so that when it is later decoded the
+authored version can be deleted.
+
+## Status
+
+| | Question | State | Answer / link |
+|---|---|---|---|
+| Q1 | keyframe time unit + ramp shape | ❔ open | blocks all animation |
+| Q2 | which build is which screen state | 🟡 partial | build 4 title, 5 main menu, 6/8/9 submenus, `palogo` splash — unconfirmed against captures |
+| Q3 | paint order for the six screens | ❔ open | runtime-solved only; declaration table is refuted |
+| Q4 | button → GamePart | ❔ open | labels are baked into sprites |
+| Q5 | navigation semantics | ❔ open | |
+| Q6 | boot sequence + what drives it | 🟡 partial | order observed; the driver is not decoded |
+| Q7 | transitions | ❔ open | |
+| Q8 | menu audio bindings | ❔ open | cue table complete, event binding is not |
+| Q9 | video binding + playback rules | 🟡 partial | `ADV.wmv` is the boot intro; new-game intro unidentified |
+| S1 | Ready Room go/no-go | ❔ open | probe not run |
+
+## Already settled — the port can rely on these today
+
+* **`GP_TITLE.pak` is the whole title-side tree.** Build 4 is the title with the
+  animating wordmarks, build 5 the five-button main menu, builds 6/8/9 are
+  submenus, and the developer splash is the `palogo` bundle in the same archive.
+  ✅ decoded (enumeration), 🟡 the state labels are not yet capture-confirmed.
+* **Buttons are identifiable as data.** Element kind `0x3002` = button, `0x0` =
+  decoration, `0x10` = primitive. ✅ decoded.
+* **Menu order is geometric.** Buttons sorted top-to-bottom by resting Y. This is
+  ✅ correct for a vertical menu and is **not** a decoded neighbour graph — the
+  disc's real navigation structure is unknown, and `opt ` is *not* a focus link
+  (measured and refuted, see
+  [`ui-focus-and-effect-elements.md`](../re/structures/ui-focus-and-effect-elements.md)).
+* **Highlighted states pair by name** — `ptbtn01.rat` ↔ `ptbtn01f.rat`. 🟡 a
+  naming convention that holds for all 54 real pairs, not a decoded field.
+* **The resting pose is the hold**, not the first, last or longest-dwell keyframe;
+  a keyframe is the **start of a ramp**.
+  [`ui-resting-pose.md`](../re/structures/ui-resting-pose.md). ✅
+* **The GamePart id table** — 29 entries at `.rdata 0x820A1630`, confirmed by the
+  executable's own registration strings. ✅ This is the screen vocabulary; which
+  button reaches which entry is Q4 and is *not* part of it.
+* **The logo splash is a screen, not a video.** `logo1`–`logo4` are
+  manifest-bound with no `.wmv` on the disc. ✅
+* **Sprites carry their own labels.** No font rendering or localisation is needed
+  for this milestone. ✅
+
+## Facts the port will trip over
+
+* **`ADV.wmv` is WMV3 video + WMA Pro audio**, 1280×720 at 30 fps, 137 s. Godot 4
+  plays only Ogg Theora natively. How to handle that is the port's decision, not
+  ours — but it is not optional.
+* **The disc holds 3.3 GB of video.** Only the boot intro and the one new-game
+  intro are in scope.
+* **`Static.slb` over-declares its size** by 616 768 bytes — it is the
+  highest-offset entry in `sound.pak` and its size field is an allocation size. A
+  reader must allow a short read there and only there.
+* **Voice downmixes to mono, music does not.** The left-channel downmix is correct
+  for spoken lines and discards half a music mix.
+* **`JNGL_001.slb` does not decode.** One bank in 9 519; its payload is not a whole
+  number of XMA1 packets from any known data offset.
+
+## Reference data
+
+Committed alongside the findings, so the port can be built without a disc in the
+loop during development:
+
+* `sylpheed-cli screen info --build <n> GP_TITLE.pak` — the element table, per
+  build, with pivots, kinds, focus links, keyframes and resting poses.
+* `sylpheed-cli screen render` — the reference composite. When the port draws a
+  screen, this is what it should be diffed against; where they disagree, one of
+  them is wrong and the disagreement is worth reporting back.
+* `docs/re/captures/` — framebuffer captures of the real screens, for anything
+  that has to be checked against the game rather than against our renderer.