docs: deployment runbook (stop guessing the deploy path)

CLAUDE.md

@@ -1,5 +1,14 @@
 # Repo conventions for Claude Code agents working in kernelCAD-web
 
+## Deployment
+
+Before deploying anything, read `docs/DEPLOY.md`. Short version: one trunk
+(`develop`, no `main`); the Studio (`src/`) auto-deploys to app.kernelcad.com on
+push to `develop`; the marketing site (`site/`, kernelcad.com) ships ONLY via a
+manual `gh workflow run deploy-kernelcad-com.yml -R w1ne/kernelCAD-server -f
+web_ref=develop`; a `v*` tag is a full npm release, not a per-surface deploy.
+Don't guess the deploy path — match the changed surface to the runbook.
+
 ## CAD authoring discipline
 
 For any task that creates or modifies CAD output, use the bundled

docs/DEPLOY.md

@@ -0,0 +1,69 @@
+# Deployment runbook
+
+Three independent surfaces ship by three different mechanisms. Match the change
+you made to the right row — do **not** cut a release tag just to push one surface.
+
+| You changed… | Surface | How it ships |
+|---|---|---|
+| `src/**` (the Studio app) | **app.kernelcad.com** | **Automatic** on push to `develop` |
+| `site/**` (landing + gallery) | **kernelcad.com** | **Manual** dispatch (see below) |
+| published packages | **npm** | A `v*` **release tag** (full release) |
+
+There is one trunk: **`develop`** (the GitHub default branch). There is no `main`.
+
+## app.kernelcad.com — the Studio
+
+- Workflow: `.github/workflows/deploy-cloudflare.yml` (job `app`).
+- Trigger: **push to `develop`** (also `main`, `feat/kernelcad-website`, `v*` tags).
+- Build: `npm run build` (Vite, `VITE_BASE_PATH=/`) → Cloudflare Pages project `kernelcad-app`.
+- **So: merging a PR to `develop` auto-deploys the Studio. No manual step.**
+
+## kernelcad.com — marketing site + gallery
+
+The marketing site source lives here under `site/`, but it is **not deployed from
+this repo**. It is deployed by a manual operator workflow in the private
+**`kernelCAD-server`** repo: `deploy-kernelcad-com.yml`.
+
+- Trigger: **`workflow_dispatch` only** (plus a self-trigger when that workflow
+  file itself changes). Content changes under `site/` do **not** auto-deploy.
+- What it does: checks out `kernelCAD-web` at `web_ref` (default `develop`), runs
+  `npm run site:build` (which runs `build-demo` + `build-gallery`), deploys the
+  built `site/` to the marketing Cloudflare Pages project, then **purges the
+  kernelcad.com edge cache** (the custom domain caches per-slug assets for hours).
+
+To deploy the current `develop` to kernelcad.com:
+
+```bash
+# after your site/ change is merged to develop
+gh workflow run deploy-kernelcad-com.yml -R w1ne/kernelCAD-server -f web_ref=develop
+# watch it:
+gh run watch -R w1ne/kernelCAD-server "$(gh run list -R w1ne/kernelCAD-server -w deploy-kernelcad-com.yml -L1 --json databaseId --jq '.[0].databaseId')"
+```
+
+`web_ref` accepts any ref (branch/tag/sha) if you need to deploy something other
+than `develop`. Operator-side detail (Pages project name, secrets) is documented
+in `kernelCAD-server/docs/deploy-*.md` and kept private on purpose.
+
+Verify after deploy (edge cache can lag if the purge step is skipped):
+
+```bash
+curl -s https://kernelcad.com/gallery.json | jq -r '.generatedAt'   # should be recent
+curl -s https://kernelcad.com/ | grep -o '<h1 class="headline">[^<]*'
+```
+
+## npm — a release tag
+
+A `v*` tag is a **full release**, not a single-surface deploy. Pushing it fires
+**all** of: `publish-npm.yml` (publishes packages to npm), `dist-skills.yml`,
+`deploy.yml` (GitHub Pages), and `deploy-cloudflare.yml`. Per the **Demo
+discipline** rule in `CLAUDE.md`, a `v0.X.0` minor tag also requires
+`docs/demos/v0.X/<task>/whats-new.md` + `meta.json`.
+
+Only tag when you intend an actual release. To ship the Studio or the marketing
+site without releasing packages, use the per-surface paths above.
+
+## Quick answers
+
+- **Changed the Studio (`src/`)** → merge to `develop`; it auto-deploys to app.kernelcad.com.
+- **Changed the landing/gallery (`site/`)** → merge to `develop`, then `gh workflow run deploy-kernelcad-com.yml -R w1ne/kernelCAD-server -f web_ref=develop`.
+- **Want to release packages** → cut a `v*` tag (mind Demo discipline for `v0.X.0`).