Wire breadcrumbs into the bread event fabric (app id crumbs)

The watch daemon publishes bread.crumbs.profile.changed and
bread.crumbs.health.changed on real transitions (not every poll tick)
and honors bread.command.crumbs.set_profile via the existing
state::set_profile path. BreadClient is fail-silent: if breadd is
down, breadcrumbs behaves exactly as before.

Document the contract in EVENTS.md. CLAUDE.md now points at
CONTRIBUTING (single-trunk, no three-branch model), bakery, and
EVENTS.md.

CLAUDE.md

@@ -0,0 +1,50 @@
+# CLAUDE.md — Repo hygiene
+
+Scope: this file covers *repo hygiene* — branching, remotes, CI, cleanup. It is not project documentation.
+
+This repo follows the branch/release workflow documented in `CONTRIBUTING.md`
+— read and follow it for any git, branch, or release work here (the
+single-trunk model, `feature/x`/`fix/x` branch naming, how RC tags work,
+etc). Don't improvise a different workflow. The short version: there is one
+long-lived branch, `main` — no `dev` or `beta` branch exists. `main`
+auto-publishes a dev-track build on every push. "Beta" and "stable" are both
+just tags, not branches: push a `vX.Y.Z-rc.N` tag to publish a beta-track
+build, push a plain `vX.Y.Z` tag to cut the signed stable release.
+"Freezing" for stabilization means pausing pushes to `main`, not moving a
+branch. This replaced an earlier three-branch (`dev`/`beta`/`main`) model
+after `main` was found to have silently rotted out of sync with `dev`/`beta`
+across most repos in this ecosystem — a manual "merge beta into main
+monthly" step nobody reliably did across a dozen-plus repos. Collapsing to
+one branch removes the class of bug; there's nothing left that can fall out
+of sync.
+
+## Remotes
+- `origin` — Forgejo (`git.breadway.dev` via Hestia, SSH) — authoritative.
+- `github` — GitHub mirror. Push both when publishing. Agents push `origin` only; the GitHub remote auto-mirrors.
+
+## Distribution
+- Bakery-only. `bakery.toml` is the product manifest; there is no
+  `packaging/arch/PKGBUILD` in this repo.
+- Tracks: `bakery track set {dev,beta,stable}` then `bakery update breadcrumbs`
+  (or `bakery update --all`). See CONTRIBUTING.md and bread-ecosystem's
+  `docs/release-channels.md`.
+
+## Events
+- Bread bus contract: `EVENTS.md`. App id is `crumbs`.
+- Fail-silent: breadcrumbs behaves the same whether `breadd` is running or
+  not. Commands (`bread.command.crumbs.*`) are only received while
+  `breadcrumbs watch` / the user systemd unit is up.
+
+## CI
+- `check.yml` — clippy + `cargo test --release` on `feature/**` and `fix/**`.
+- `dev-release.yml` — triggered on push to `main` (dev-track bakery publish).
+- `rc-release.yml` — triggered on any `vX.Y.Z-rc.N` tag push (beta track).
+- `release.yml` — triggered on any other `v*` tag push (signed stable).
+
+All CI runs on a self-hosted runner. No build/lint/test CI runs on ordinary
+commits or PRs to `main` beyond the dev-track workflow above.
+
+## Don't
+- Don't embed credentials in remote URLs — SSH or a credential helper only.
+- Don't invent bread command verbs that have no real breadcrumbs feature
+  behind them. See EVENTS.md.