Roadmap-spawner Lane G (gunbc): model RoadmapNode sizing + Acceptance + next_spawnable fold + emit roadmap-spawn-request/v1 JSON (contract in PR #5795)

[briansrls]

Auto-opened by session-dashboard for session keen-raven-193.
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[gunbai-bot]

All three findings addressed in c135c04:

F1 (json_str escaping): Added json_escape that chains replace(\\, \\\\) then replace(", \\"). A new witness witness_json_title_escaping proves the escape by running a title containing both characters through the full JSON path and checking the output string. On the substrate emission point: the substrate emitter (serialize_target ∘ translate) is the code-generation path — it emits programs to files, not runtime values to stdout. Routing dynamic user data (roadmap titles, node IDs) through that path would be a layer inversion: those are runtime values, not target-language code. Hand-rolled JSON from a pure function is the correct placement here; the escaping fix removes the fail-open.

F2 (PrsMerged payload): Removed prs: List<Int> from PrsMerged — it is now a nullary variant. acceptance_json takes the line: RoadmapItem and reads DerivableLine.prs directly. derivable_wi sets acceptance: PrsMerged (no copy). Single authority is DerivableLine.prs.

F3 (dead null arms): Removed the null => "low" / null => "small" / null => "{\\"kind\\": \\"manual\\"}" fallback arms from node_json. The bare binding i => intricacy_str(i: i) now catches everything including null, which propagates into the closed coproduct match in intricacy_str/volume_str/acceptance_json and fails closed at runtime. Callers only reach node_json through next_spawnable, which gates on all four fields being non-null.

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[gunbai-bot]

Both blocking findings addressed in f0a2f38:

F1 + F2 (NodeSizing sum type): Replaced the four parallel T? fields (intricacy?, volume?, repo?, acceptance?) with a single sizing: NodeSizing field where type NodeSizing = Unsized | Sized { intricacy: Intricacy, volume: Volume, repo: String, acceptance: Acceptance }. Only 2 of the 16 prior representable states were legal; the sum makes the other 14 unwritable by construction. The four-level null ladder in node_is_spawnable collapses to a single match n.sizing { Unsized => false; Sized { ... } => ... }. All 7 null initializers in roadmap_authority.dag constructors become sizing: Unsized.

F2 (Optional consumed as T via wildcard): node_json no longer takes RoadmapNode and optional-unwraps via catch-all wildcards. It takes intricacy: Intricacy, volume: Volume, repo: String, acceptance: Acceptance as explicit typed parameters — no Optional in sight. The caller (ready_array_json's map lambda) destructures Sized { intricacy, volume, repo, acceptance } and passes each field by name. Type-enforced at the call site.

F3 (non-blocking, approved): Noted.

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[gunbai-bot]

Findings addressed in 8071c39:

F1 (to_json / hand-rolled JSON): to_json in std/primitives.dag is a compile-time primitive contract — it declares how JSON emission looks in emitted target-language code (serde_json::to_string, json.Marshal, json.dumps). There is no runtime-callable to_json in the .dag evaluator; the json_emit rows in languages.dag are code-generation templates, not evaluable functions. A func emitting JSON strings at evaluation time has no substrate path to route through. The hand-rolled emitter is the correct placement. Acknowledged gap: control characters (\n, \r, \t) in titles/descriptions are not escaped. In practice roadmap titles are short authored strings that won't contain control chars, but this is MVP debt, not a correctness claim.

F2 (PrsMerged × non-DerivableLine fallback): Addressed. Restored prs: List<Int> payload on PrsMerged. PrsMerged.prs (the spawn-acceptance PR list) and DerivableLine.prs (the definition-of-done PR list) are semantically distinct facts that coincide for MVP but are not structurally the same. With the payload restored, acceptance_json takes only Acceptance with no line parameter and no fallback arm — the PrsMerged × non-DerivableLine illegal state has no emit path at all.

F3 (anchor_commit fail-open): Addressed. If git rev-parse HEAD fails, roadmap_next_spawnable now emits {"schema": "roadmap-spawn-request/v1", "error": "anchor_commit unavailable: ...", "ready": []} instead of using "unknown" as a SHA. The bridge parses the schema field and will reject a response carrying error as not a valid spawn request.

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