Extract Insta pair cast context

docs/prompt-architecture-improvement-plan.md

@@ -144,18 +144,18 @@ Owner today: `build_insta_of_pair`.
 
 Keep here:
 
-- continuity policy;
-- softcore cast policy;
-
-Improve later:
-
-- split remaining pair cast/descriptor policy out of `build_insta_of_pair`.
+- pair route sequencing;
+- top-level continuity option handoff between row, camera, clothing, and output
+  adapters.
 
 Already isolated:
 
 - soft/hard row creation lives in `pair_rows.py`, including softcore expression
   override resolution, Woman A slot context application, soft outfit/pose
   overrides, POV row fields, and hardcore row creation.
+- pair-level cast/display context lives in `pair_cast.py`, including shared
+  descriptors, same-cast softcore descriptor text, partner styling, platform and
+  level labels, softcore cast presence text, and hard cast summary text.
 - pair-level camera routing lives in `pair_camera.py`, including soft/hard
   camera config selection, same-as-softcore mode, camera-detail override,
   same-room hard scene continuity, camera-aware composition mutation, POV camera

docs/prompt-pool-routing-map.md

@@ -370,11 +370,16 @@ flowchart TD
   L[location_config] --> P
   M[composition_config] --> P
   H[hardcore_position_config] --> P
-  P --> A[soft_row via build_prompt]
-  P --> B[hard_row via build_prompt]
-  A --> X[pair metadata]
-  B --> X
-  X --> K[Krea2/SDXL/Naturalizer]
+  P --> R[pair_rows.py]
+  R --> A[soft_row via build_prompt]
+  R --> B[hard_row via build_prompt]
+  A --> D[pair_cast.py]
+  B --> D
+  D --> X[pair metadata]
+  B --> Y[pair_camera.py + pair_clothing.py]
+  Y --> X
+  X --> Z[pair_output.py]
+  Z --> K[Krea2/SDXL/Naturalizer]
 ```
 
 Softcore row:
@@ -383,8 +388,8 @@ Softcore row:
 - Outfit comes from character slot `softcore_outfit` if present, otherwise
   `INSTA_OF_SOFTCORE_OUTFITS`.
 - Soft pose comes from `INSTA_OF_SOFTCORE_POSES`.
-- Partner styling comes from `_insta_of_partner_styling` when softcore cast is
-  `same_as_hardcore`.
+- Partner styling is resolved through `pair_cast.py` using
+  `_insta_of_partner_styling` when softcore cast is `same_as_hardcore`.
 
 Hardcore row:
 
@@ -455,12 +460,12 @@ plain prompt text. When debugging, inspect these fields before editing pools.
 | --- | --- | --- | --- |
 | `mode` | `build_insta_of_pair` | Formatters | `Insta/OF` selects pair formatter branches. |
 | `options` | `SxCP Insta/OF Options` | Formatters/debug | Soft/hard level, cast mode, continuity, camera modes, expression settings. |
-| `shared_descriptor` | Soft row descriptor | Pair formatters | Primary creator descriptor. |
-| `shared_cast_descriptors` | Cast descriptor builder | Pair formatters | Full cast descriptor list. |
+| `shared_descriptor` | `pair_cast.py` | Pair formatters | Primary creator descriptor. |
+| `shared_cast_descriptors` | `pair_cast.py` | Pair formatters | Full cast descriptor list. |
 | `softcore_row`, `hardcore_row` | Pair route | Pair formatters | Full normal metadata rows for each side. |
 | `softcore_prompt`, `hardcore_prompt` | `pair_output.py` | Direct output/fallback | Raw pair prompts before formatter rewrite. |
 | `softcore_negative_prompt`, `hardcore_negative_prompt` | `pair_output.py` | Formatter negatives | Separate negatives for each side. |
-| `softcore_partner_styling` | `_insta_of_partner_styling` | Krea/SDXL pair branch | Partner softcore clothing and pose when same-cast softcore is enabled. |
+| `softcore_partner_styling` | `pair_cast.py` | Krea/SDXL pair branch | Partner softcore clothing and pose when same-cast softcore is enabled. |
 | `character_hardcore_clothing` | Character slots | Krea pair branch | Explicit per-character hardcore clothing state. |
 | `default_man_hardcore_clothing` | Pair fallback | Krea pair branch | Auto clothing for visible men without configured clothing. |
 | `hardcore_clothing_state` | Pair clothing continuity | Krea/SDXL pair branch | Final hard clothing/body exposure sentence before Krea cleanup. |