refactor(lite): remove dead backend artifact-contract/resolver scaffold

lite_backend_artifact_{contract,resolver}.{cpp,h} (~1,960 lines) were
app-linked but never invoked: all 14 public entry points
(evaluateLiteBackendArtifactContract/Resolver, evaluateLiteBackendActivation-
Readiness, the resolve*/...Name helpers) had zero callers in the app, the
lite_smoke tool, build scripts, or surviving tests. The real backend load
path (LiteClientBridge::linkedSdxl) uses direct litelib_* externs, and the
DRAGONX_ENABLE_LITE_BACKEND symbol check is done in CMake against the symbols
inventory (FATAL_ERROR on a missing symbol) — not via these C++ files. The
files were saturated with churn markers (disabled / dry-dispatch / scaffold).

- Delete the four artifact files and their 8 CMakeLists references.
- Drop the orphaned test cruft in test_phase4.cpp: the contract include,
  5 type aliases, and 3 never-called helpers (heapConstructPlanResult,
  makeReadyLiteBackendArtifactProvenance, liteBackendArtifactContractHasIssue)
  left over from the already-removed bridge-runtime tests.
- Correct the CLAUDE.md lite-wallet description (it credited these files with
  backend validation that CMake actually performs) and drop the stale
  lite_bridge_runtime mention.

Both variants build; full test suite passes; source-hygiene check clean.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

CLAUDE.md

@@ -51,7 +51,7 @@ There is no per-test filtering — it is one binary that runs every assertion. T
 
 **UI** (`src/ui/`): `windows/` are the tabs and dialogs (one pair per screen, e.g. `send_tab`, `mining_tab`, `console_tab`), `pages/` are multi-section screens (Settings), `screens/` are layout headers, `material/` is the design-system layer, `schema/` loads the TOML UI schema/skins, `effects/` is GL post-processing (blur/acrylic).
 
-**Lite wallet** (`src/wallet/`): the bridge to an external `litelib_*` C-ABI backend (`lite_client_bridge`, `lite_bridge_runtime`, `lite_connection_service`, `lite_sync_service`, result parsers, and the artifact-contract/resolver that validates a prebuilt backend library). The real frontend entry points are `lite_wallet_lifecycle_ui_adapter` and `lite_wallet_server_selection_adapter` (used by `src/ui/pages/settings_page.cpp`); everything else is reachable through them.
+**Lite wallet** (`src/wallet/`): the bridge to an external `litelib_*` C-ABI backend. `lite_client_bridge` loads the backend (via direct `litelib_*` externs in `linkedSdxl()`) and owns each Rust string through `lite_owned_string` (copy-before-free / free-once). On top sit `lite_connection_service`, `lite_sync_service`, `lite_result_parsers`, `lite_wallet_gateway`, `lite_wallet_state_mapper`, and `lite_wallet_lifecycle_service`, all driven by `lite_wallet_controller`. The real frontend entry points are `lite_wallet_lifecycle_ui_adapter` and `lite_wallet_server_selection_adapter` (used by `src/ui/pages/settings_page.cpp`); everything else is reachable through them. (The prebuilt-backend symbol check for `DRAGONX_ENABLE_LITE_BACKEND` is done in CMake against the symbols inventory — see below — not in C++.)
 
 > ⚠️ **Do not regrow the `_plan`/`_batch` churn.** This directory previously held ~160 dead `lite_wallet_*_plan` / `*_batch*_receipt_custody_acceptance_confirmation_archive_handoff_*` files (filenames up to 250 chars) — auto-generated scaffolding that never reached the shipping binary. They were deleted. When extending lite-wallet behavior, **edit the named service/bridge/runtime files in place**; never add another "promotion/receipt/custody/handoff/stewardship" wrapper layer. `scripts/check-source-hygiene.sh` (wired as a `.git/hooks/pre-commit` hook) blocks >80-char filenames and chained churn-token names — run it in CI too.