chore(tasks): add TASK-223 release blocker for WASM Zig 0.15 verification

Author: subtleGradient

.tasks/backlog/TASK-209-release-0.16.300-preview.md

@@ -37,6 +37,8 @@ This list is intended to be exhaustive. Each blocker must have an owning task ca
 - [x] **WASM build works on current Zig toolchain and is reproducible in CI**.
   - Task: `.tasks/done/TASK-212-fix-wasm-build-for-release.md`
   - Status: DONE (Round 77) — Zig 0.15 compat fixed
+- [ ] **Verify WASM build uses Zig 0.15** (not 0.14).
+  - Task: `.tasks/triage/TASK-223-verify-wasm-uses-zig-0.15.md`
 - [x] **Browser bundle uses local CR-SQLite WASM (not CDN sql.js)**.
   - Task: `.tasks/done/TASK-213-browser-provider-loads-crsqlite-wasm.md`
   - Status: DONE (Round 77) — no CDN dependency, 30/30 browser tests pass

.tasks/triage/TASK-223-verify-wasm-uses-zig-0.15.md

@@ -0,0 +1,40 @@
+# TASK-223 — Verify WASM Build Uses Zig 0.15
+
+## Goal
+Ensure the WASM build uses Zig 0.15 (not 0.14) and that CI/release workflows reference the correct toolchain.
+
+## Status
+- State: triage
+- Priority: HIGH (release blocker)
+- Created: 2025-12-26
+- Triggered by: Tom's request to verify WASM toolchain version
+
+## Context
+The release scope for `0.16.300-preview` includes Native + WASM + Browser. Round 77 fixed WASM build compatibility for Zig 0.15 (TASK-212), but we need to verify:
+1. The WASM build actually uses Zig 0.15 (not 0.14)
+2. CI workflows reference Zig 0.15
+3. Build scripts don't have hardcoded 0.14 references
+
+## Files to Verify
+- `zig/build.zig` — WASM target configuration
+- `zig/wasm-build/build-sqlite-wasm.sh` — WASM build script
+- `.github/workflows/zig-tests.yaml` — CI workflow
+- `.github/workflows/publish.yaml` — Release workflow
+- `flake.nix` — Nix toolchain version
+
+## Acceptance Criteria
+1. [ ] `nix run nixpkgs#zig -- version` returns 0.15.x
+2. [ ] WASM build succeeds with Zig 0.15: `cd zig && nix run nixpkgs#zig -- build wasm`
+3. [ ] No references to Zig 0.14 in build scripts or CI workflows
+4. [ ] CI workflows use Zig 0.15 (or nixpkgs default which is 0.15)
+
+## Parent Docs / Cross-links
+- Release tracker: `.tasks/backlog/TASK-209-release-0.16.300-preview.md`
+- WASM build fix: `.tasks/done/TASK-212-fix-wasm-build-for-release.md`
+- Release decision: `.wishes/blocked-on-tom/release-readiness-decision.md`
+
+## Progress Log
+- 2025-12-26: Created as release blocker per Tom's request.
+
+## Completion Notes
+(Empty until done.)

research/zig-cr/92-gap-backlog.md

@@ -66,11 +66,12 @@ No active tasks.
 - [x] **TASK-219**: Test suite review ✓ — 72 tests, blind spots documented
 - [x] **WF-028**: Empty BLOB PK encoding ✓ — fixed in api.zig bind_blob()
 
-### Triage Inbox (4 items)
+### Triage Inbox (5 items)
 | Task | Priority | Summary | Disposition |
 |------|----------|---------|-------------|
 | **TASK-220** | HIGH | Verify CI passes after re-enable | Release blocker (verification) |
 | **TASK-222** | HIGH | Browser test failure investigation | Release blocker (transient?) |
+| **TASK-223** | HIGH | Verify WASM build uses Zig 0.15 | Release blocker (toolchain) |
 | **TASK-200** | LOW | Zig validation gaps (more permissive) | Nice to have |
 | **TASK-201** | LOW | Performance regression tests | Nice to have |