Complete 9 parallel tasks: mesh specs + Zig npm packaging + release planning

Spec Phase 1 (7 tasks):
- TASK-039: Global mesh package map (10 new packages proposed)
- TASK-040: crsql-mesh-protocol (message types)
- TASK-041: crsql-mesh core sync engine
- TASK-042: crsql-mesh-transport (pluggable transports)
- TASK-043: crsql-mesh-integration (existing package changes)
- TASK-044: libcrsql-next (Zig artifact transition)
- TASK-045: crsql-mesh-runtime (platform adapters)

Infrastructure (2 tasks):
- TASK-034: npm packaging for Zig-built extensions
  - Added implementation selection (CRSQLITE_IMPL env var)
  - New build scripts: build-zig.sh, bundle-zig-lib.sh
  - Bundled macOS Zig artifacts (arm64, x86_64, universal)
  - Extended dist.test.ts for Zig verification
- TASK-036: Release planning proposal
  - research/zig-cr/103-release-planning-proposal.md
  - 4-stage rollout: browser beta → linux → mac/win → stable

All task cards moved to .tasks/done/

Author: subtleGradient

.tasks/backlog/TASK-034-npm-package-zig-native.md

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+# TASK-034: npm Packaging for Zig-built Native Extensions
+
+## Status
+- [ ] Planned
+- [ ] Assigned
+- [ ] In Progress
+- [ ] Blocked (reason: ...)
+- [x] Complete
+
+## Priority
+high
+
+## Assigned To
+subagent (general)
+
+## Parent Docs / Cross-links
+- Gap backlog: `research/zig-cr/92-gap-backlog.md` ("Cross-platform Packaging & CI" / "Remaining Work for Production Release")
+- Existing JS package entry: `index.js`, `package.json`, `scripts/*`
+- Existing prebuilt artifacts: `lib/`
+- Zig build artifacts: `zig/zig-out*/lib/libcrsqlite.*`
+
+## Description
+Package Zig-built native artifacts in the main npm package so users can install and load Zig `crsqlite` without building from source.
+
+This repository already ships C/Rust prebuilt artifacts in `lib/`. Extend or parallel that mechanism for Zig builds.
+
+Constraints:
+- Do not introduce a new TS project; stay within existing build tooling.
+- Prefer reproducible builds (Nix).
+
+## Files to Modify
+- `package.json`
+- `scripts/*` (likely `scripts/build-production.ts` / `scripts/build-production.cjs`)
+- `index.js` (if selection logic changes)
+- `lib/*` (only if intentionally adding artifacts)
+- `research/zig-cr/92-gap-backlog.md` (status notes)
+
+## Acceptance Criteria
+- [x] Build pipeline produces Zig artifacts for at least one platform and places them in a deterministic location.
+- [x] Runtime loader can select Zig artifacts deterministically (or explicitly documents why it can't yet).
+- [x] `dist.test.ts` (or equivalent existing packaging sanity tests) extended to assert Zig artifacts presence/selection.
+- [x] No regression in existing C/Rust artifact selection.
+
+## Progress Log
+### 2025-12-14
+- Task created during gap review; not yet started
+
+### 2025-12-14 (Implementation)
+- Updated `index.js` with implementation selection logic:
+  - New `PREFER_IMPLEMENTATION` export (controlled by `CRSQLITE_IMPL` env var)
+  - `getExtensionPath()` now accepts `{ implementation: 'zig' | 'c-rust' | 'auto' }` option
+  - Default 'auto' mode prefers Zig, falls back to C/Rust
+- Updated `index.d.ts` with new types and exports
+- Created `scripts/build-zig.sh` - builds Zig extension for various platforms
+- Created `scripts/bundle-zig-lib.sh` - bundles Zig artifacts to `lib/` with naming convention `crsqlite-zig-<platform>-<arch>.<ext>`
+- Updated `package.json` with new scripts:
+  - `build:zig` - build for current platform
+  - `build:zig:all` - build all platforms
+  - `bundle-lib:zig` - bundle Zig artifacts to lib/
+  - `test:zig` - run packaging tests
+- Updated `dist.test.ts` with Zig artifact verification tests
+- Bundled macOS Zig artifacts (universal, aarch64, x86_64) to lib/
+- All tests pass:
+  - Loader correctly prefers Zig artifacts in 'auto' mode
+  - Explicit implementation selection works
+  - No regression in C/Rust artifact selection logic
+
+## Completion Notes
+**Completed 2025-12-14**
+
+Changes made:
+1. `index.js` - Added implementation selection (zig/c-rust/auto)
+2. `index.d.ts` - Added new types for implementation selection
+3. `scripts/build-zig.sh` - New script to build Zig extension cross-platform
+4. `scripts/bundle-zig-lib.sh` - New script to bundle Zig artifacts to lib/
+5. `package.json` - Added new npm scripts for Zig builds
+6. `dist.test.ts` - Extended with Zig artifact verification
+
+Naming convention:
+- C/Rust: `crsqlite-<platform>-<arch>.<ext>`
+- Zig: `crsqlite-zig-<platform>-<arch>.<ext>`
+
+Artifacts in lib/:
+- `crsqlite-zig-darwin-universal.dylib` (macOS universal)
+- `crsqlite-zig-darwin-aarch64.dylib` (macOS ARM64)
+- `crsqlite-zig-darwin-x86_64.dylib` (macOS x64)
+- Linux artifacts can be built with `npm run build:zig linux && npm run bundle-lib:zig linux`

.tasks/backlog/TASK-036-release-planning-proposal.md

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+# TASK-036: Release Planning Proposal (Where + How)
+
+## Status
+- [x] Planned
+- [x] Assigned
+- [x] In Progress
+- [ ] Blocked (reason: ...)
+- [x] Complete
+
+## Priority
+medium
+
+## Assigned To
+subagent (general)
+
+## Parent Docs / Cross-links
+- Wish: `.wishes/release-planning.md`
+- Current packages: `package.json`, `zig/browser-dist/package.json`
+- CI: `.github/workflows/*`
+- **Proposal:** `research/zig-cr/103-release-planning-proposal.md`
+
+## Description
+Write a proposal for how/where to release the Zig work (native + browser):
+
+- Which registries/channels: Nix, npm, GitHub releases, etc.
+- What versioning strategy: aligned with root package version or independent
+- What artifact matrix: darwin arm64/x64, linux x64/arm64, windows, wasm
+- What docs are needed and where they live (prefer in-repo, near code)
+
+Do not publish anything. Output should be a checklist and a proposed staged rollout.
+
+## Files to Modify
+- `research/zig-cr/*` (small proposal doc) or `README.md` (if appropriate)
+- `.wishes/release-planning.md` (mark done + link to proposal)
+
+## Acceptance Criteria
+- [x] Proposal enumerates channels + pros/cons.
+- [x] Proposal has a staged plan (MVP web beta → linux → mac/windows, etc.).
+- [x] Proposal lists concrete next engineering tasks and where they live in `.tasks/`.
+
+## Progress Log
+### 2025-12-14
+- Task created during gap review; not yet started
+- Analyzed existing package structure and distribution
+- Researched competitor distribution patterns (better-sqlite3, sql.js, libsql)
+- Wrote comprehensive proposal at `research/zig-cr/103-release-planning-proposal.md`
+- Updated `.wishes/release-planning.md` with completion notes
+- Task complete
+
+## Completion Notes
+
+**Completed:** 2025-12-14
+
+**Deliverables:**
+1. `research/zig-cr/103-release-planning-proposal.md` - Full release planning proposal
+
+**Key Recommendations:**
+- **Primary channel:** npm with platform-specific optional dependency packages (follow better-sqlite3 model)
+- **Secondary channels:** GitHub Releases for raw binaries, Nix flakes for reproducible builds
+- **Versioning:** Aligned versions across all packages (e.g., 0.17.0)
+- **Staged rollout:** Browser beta (week 1) -> Linux (week 2) -> macOS/Windows (week 3) -> Stable (week 4)
+
+**Next Tasks Identified:**
+- TASK-037: Publish browser package to npm beta
+- TASK-038: Set up Zig Linux CI builds
+- TASK-039: Create platform-specific npm packages
+- TASK-040: Update root README for Zig transition
+- TASK-041: Write browser package README
+- TASK-042: Create GitHub Release workflow