feat: add generated scene skill platform hardening

docs/superpowers/specs/2026-04-19-boundary-runtime-prerequisites-roadmap-design.md

@@ -0,0 +1,57 @@
+# Boundary Runtime Prerequisites Roadmap Design
+
+> Date: 2026-04-19
+> Status: Draft
+> Upstream Decision: [2026-04-19-post-g7-boundary-decision-report.md](D:/data/ideaSpace/rust/sgClaw/claw-new/docs/superpowers/reports/2026-04-19-post-g7-boundary-decision-report.md)
+
+## 1. Intent
+
+This design defines the next bounded slice after the post-`G7` boundary decision selects `prerequisites-only hold`.
+
+The target is:
+
+`boundary runtime prerequisites roadmap`
+
+## 2. Why This Direction
+
+This direction is selected because:
+
+1. `G7` is already closed and should not be reopened
+2. `G6` still depends on stronger host-bridge real execution semantics
+3. `G8` still depends on local document runtime and attachment handling
+4. forcing either family into execution now would exceed the bounded next-step budget
+
+## 3. Scope Boundary
+
+This design is limited to prerequisite scoping only.
+
+It may include:
+
+1. separating `G6` prerequisite pressure from `G8` prerequisite pressure
+2. defining the minimum prerequisite slice needed before either family can enter real-sample scope
+3. selecting one bounded prerequisite direction
+
+It must not include:
+
+1. executing `G6` or `G8`
+2. implementing host-runtime or local-doc runtime directly
+3. reopening `G7`
+4. reopening `G1-E / G2 / G3`
+5. opening `G4 / G5`
+
+## 4. Target Outcome
+
+The bounded target outcome is one of two states:
+
+1. a selected prerequisite direction for `G6`
+2. or a selected prerequisite direction for `G8`
+
+The design rejects direct family execution under this slice.
+
+## 5. Exit Condition
+
+This design is complete when implementation can be bounded to one roadmap that:
+
+1. compares `G6` and `G8` prerequisite burden directly
+2. selects exactly one prerequisite direction
+3. publishes one bounded follow-up plan