chore: remove unused desktop app, cloud deployment infra, and monitoring stack

Deletes desktop/ (Electron wrapper), deployments/ (Helm/Kustomize/
Terraform/CI for cloud deploy), and monitoring/ (Prometheus + Grafana
stack) along with DESKTOP.md, DEPLOYMENT.md, docker-compose.full.yml,
their npm scripts, and every dangling reference across README,
ARCHITECTURE, INSTALL, SETUP, docs/, and the repeated per-file
MODULE_GUIDE "Observability" boilerplate comment. The GET /api/metrics
endpoint itself is untouched — it's the dashboard's own route, not
part of the removed monitoring stack.

README.md

@@ -138,8 +138,7 @@ Both must be green before a commit; the pre-commit hook runs them plus Prettier.
 | `client/` | React 18 + Vite + Tailwind dashboard |
 | `bin/ccam.js` | CLI |
 | `mcp/` | MCP server exposing read-only dashboard tools |
-| `desktop/` | Electron wrapper that embeds the server |
-| `docs/` | Architecture, API, lanes, database, deployment |
+| `docs/` | Architecture, API, lanes, database |
 | `plugins/` | Claude Code plugins shipped with the dashboard |
 
 ## Docs
@@ -148,5 +147,5 @@ Both must be green before a commit; the pre-commit hook runs them plus Prettier.
 - [`docs/LANES.md`](docs/LANES.md) — lanes, pipelines, stage detection
 - [`docs/API.md`](docs/API.md) — REST endpoints (`openapi.yaml` is generated)
 - [`docs/DATABASE.md`](docs/DATABASE.md) — tables and migrations
-- [`INSTALL.md`](INSTALL.md) · [`DEPLOYMENT.md`](DEPLOYMENT.md) · [`DESKTOP.md`](DESKTOP.md)
+- [`INSTALL.md`](INSTALL.md)
 - [`CLAUDE.md`](CLAUDE.md) — the rules an agent working in this repo must follow