Embed WASM runtime: Linux GTK + CLI Rust clients (traverse-starter + doc-approval)

[enricopiovesan]

Summary

Migrate Embed WASM runtime: Linux GTK + CLI Rust clients (traverse-starter + doc-approval) from HTTP dev sidecar to embedded in-app Traverse host, bundled manifests + WASM at build time.

Why

Phase 3 production architecture. Native UI stays platform-specific; only runtime wiring changes.

Depends on

• Traverse #553 embeddable host SDK for this platform slice
• Shared client package issues Extract TraverseCore Swift package shared between ios-swift and macos-swift #58/Extract DocApprovalCore Swift package: shared iOS + macOS client #72 (Swift) or Extract traverse-core-rs: shared Rust HTTP/SSE crate for linux-gtk and cli-rust #59/Extract doc-approval-core-rs: shared Rust crate for linux-gtk + cli-rust #73 (Rust) where applicable
• Multi-capability workflow manifests

Blocked by

• Traverse #553

Definition of Done

• App launches and executes multi-capability workflow without traverse-cli serve
• HTTP sidecar code removed from production path (may remain behind dev flag until cutover)
• Native UI unchanged in IA; Zone 1 shows Embedded runtime status
• Unit tests use host SDK test doubles, not fake business logic
• Platform build + tests pass locally

Validation

• Platform-specific build/test commands from docs/quality-standards.md
• Manual: install app → submit → pipeline output renders