docs: specs for binary distribution pipeline + per-peer capabilities

Capture the design for the two tier-2 items that weren't shipped inline
in alpha.28 — both require CI/infrastructure work (GitHub Actions,
Homebrew tap, winget manifest) or broker schema migration that's safer
to do as a separate PR with feature flag rollout.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.artifacts/specs/2026-04-15-cli-distribution-pipeline.md

@@ -0,0 +1,58 @@
+# CLI Distribution Pipeline
+
+## Status
+- Shell installer (`/install`): ✅ live, needs polish
+- Single-binary build script (`scripts/build-binaries.ts`): ✅ written, not wired to CI
+- GitHub Releases publish: ❌ not set up
+- Homebrew tap: ❌ not set up
+- winget manifest: ❌ not set up
+
+## Shipped this session (alpha.28)
+- `bun build --compile` script at `apps/cli-v2/scripts/build-binaries.ts` produces
+  `dist/bin/claudemesh-{darwin,linux,windows}-{x64,arm64}` locally.
+- `/install` updated to use the one-command `claudemesh <invite-url>` flow.
+- `claudemesh url-handler install` registers the `claudemesh://` scheme on the three OSes.
+
+## What's missing
+
+### 1. GitHub Actions to build + publish binaries
+```yaml
+# .github/workflows/release-binaries.yml
+on: { push: { tags: ['v*'] } }
+jobs:
+  build:
+    strategy: { matrix: { target: [darwin-x64, darwin-arm64, linux-x64, linux-arm64, windows-x64] } }
+    steps:
+      - uses: oven-sh/setup-bun@v2
+      - run: cd apps/cli-v2 && bun install --frozen-lockfile
+      - run: cd apps/cli-v2 && bun run scripts/build-binaries.ts
+      - uses: softprops/action-gh-release@v2
+        with: { files: apps/cli-v2/dist/bin/* }
+```
+
+### 2. `/install` detects missing Node and downloads a binary
+Current `/install` requires Node 20+. Next iteration: detect absence, curl the
+right binary from GitHub Releases, drop it in `~/.claudemesh/bin/`, add to PATH.
+
+### 3. Homebrew tap (`homebrew-claudemesh`)
+Separate repo with a formula that points at the GitHub Release artifact.
+Users: `brew install alezmad/claudemesh/claudemesh`. Auto-updated by the
+release workflow via `brew bump-formula-pr`.
+
+### 4. winget manifest
+YAML in `microsoft/winget-pkgs` repo pointing at the Windows .exe.
+
+### 5. Auto-update in-CLI
+Already have `showUpdateNotice`. Upgrade to offer `claudemesh upgrade` that
+re-runs `/install` OR downloads a new binary in place.
+
+## Why this matters
+Current state: users need Node, npm, and patience. Goal state:
+```
+curl -fsSL claudemesh.com/install | sh
+```
+…and that's it, on any OS, with or without Node.
+
+## Priority
+After tier-1 usability (done), this is the next biggest lever for adoption.
+Estimate: 1-2 days for full pipeline, mostly CI config + release testing.