Steps 1991-1993: AST sidecar lifecycle + schema stub fixes + IR chain

Step 1991: Wire AST sidecar lifecycle hooks
- openFile (DispatchPart2.h): auto-calls loadSidecarAST() after parse,
  returns annotationsRestored + staleAnnotations
- saveBuffer (DispatchPart3.h): auto-calls saveSidecarAST() +
  saveSemannoSidecar() after write, returns annotationsSaved +
  sidecarPath + semannoPath

Step 1992: Fix 9 schema stubs in Sprint 142/143/144 tool registrations
- All 9 text/AST sync and merge tools now have proper inputSchema with
  required id and documented optional parameters (language, text, mode)

Step 1993: Fix ingest_legacy_to_ir → generate_cpp_from_ir chain
- ingest_legacy_to_ir now emits ir field (SemanticCoreIR format)
  alongside existing graph/api_intent/assumption/readiness fields
- RecoveryNode → IRNode mapping: intent→kind, confidence in metadata
- Neighbor lists become inferred edges; moduleId = "legacy:" + slug
- generate_cpp_from_ir now accepts result["ir"] directly

15/15 tests passing across all three steps.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

HANDOFF-2026-03-24.md

@@ -0,0 +1,97 @@
+# Whetstone Handoff — 2026-03-24
+
+## Session Summary
+
+Three steps completed, all closing B-run pipeline gaps discovered during the
+whimptk Sprint 03 A/B test.
+
+---
+
+## Step 1991 — AST sidecar lifecycle hooks (COMPLETE)
+
+**What**: `openFile` and `saveBuffer` were the right abstraction points for
+automatic sidecar round-trips, but they never called the sidecar functions.
+Two targeted edits closed the gap:
+
+- `DispatchPart2.h` — `openFile` now calls `loadSidecarAST()` after parse,
+  returns `annotationsRestored` + `staleAnnotations` in result.
+- `DispatchPart3.h` — `saveBuffer` now calls `saveSidecarAST()` +
+  `saveSemannoSidecar()` after file write, returns `annotationsSaved`,
+  `sidecarPath`, `semannoPath` in result.
+
+5/5 tests passing (`step1991_test.cpp`).
+
+---
+
+## Step 1992 — Schema stub fix for Sprint 142/143/144 tools (COMPLETE)
+
+**What**: 9 tools registered with empty `{}` schemas — MCP clients couldn't
+discover the `id` parameter. All returned `"id required"` when called without
+schema guidance.
+
+**Files patched:**
+- `RegisterSprint142Tools.h` — `sync_text_to_ast`, `get_sync_diagnostics`,
+  `get_sync_identity_report`
+- `RegisterSprint143Tools.h` — `regenerate_text_from_ast`,
+  `preview_regenerated_diff`, `get_regeneration_decisions`
+- `RegisterSprint144Tools.h` — `detect_text_ast_conflicts`,
+  `preview_text_ast_merge`, `apply_text_ast_merge`
+
+All 9 now have proper `required: [id]` schemas with `language`/`text`/`mode`
+optional properties and useful descriptions.
+
+5/5 tests passing (`step1992_test.cpp`).
+
+---
+
+## Step 1993 — `ingest_legacy_to_ir` → `generate_cpp_from_ir` chain fix (COMPLETE)
+
+**What**: `ingest_legacy_to_ir` returned `{graph, api_intent, assumption, ...}`
+but `generate_cpp_from_ir` expected `{ir: SemanticCoreIR}`. The B-run got
+`ir_invalid` because the formats were incompatible.
+
+**Fix**: `RegisterLegacyIngestionTools.h` — added `buildIRFromGraph()` helper
+that maps `RecoveryNode` objects to `IRNode`/`IREdge` and constructs a valid
+`SemanticCoreIR`. The `ir` field is now emitted alongside the existing output:
+
+```
+result = ingest_legacy_to_ir({source: "...", language: "cpp"})
+generate_cpp_from_ir({ir: result["ir"], profile: "safe-first"})  // works
+```
+
+Mapping: `core` → Module, `api_inference` → Function, `assumed` → Effect,
+`unknown` → Unknown. Neighbors become `{relation: "inferred"}` edges with
+existence check. `moduleId` = `"legacy:" + source.substr(0, 32)`.
+
+5/5 tests passing (`step1993_test.cpp`).
+
+---
+
+## What's Still Open
+
+From the original B-run gap list, both gaps are now closed:
+- ~~Schema stubs~~ (Step 1992) ✓
+- ~~IR chain mismatch~~ (Step 1993) ✓
+
+The whimptk Sprint 03 B-run pipeline is now unblocked end-to-end:
+```
+ingest_legacy_to_ir → ir field → generate_cpp_from_ir → files
+```
+
+The next time whimptk Sprint 04 runs, use the proper pipeline:
+1. `start_recording`
+2. `architect_intake` (spec with Goals/Constraints/Acceptance Criteria sections)
+3. `generate_taskitems`
+4. `queue_ready`
+5. `ingest_legacy_to_ir` on any legacy header
+6. `generate_cpp_from_ir` using `result["ir"]`
+7. `apply_text_ast_merge` + `save_buffer` to finalize
+8. `get_metrics`
+
+---
+
+## Build State
+
+- `whetstone_mcp` binary: `editor/build-native/whetstone_mcp` (rebuilt)
+- All prior tests still passing (architecture gate unaffected)
+- Daemon: restart with `tools/start-whetstone-daemon.sh` if needed