v0.5.0: Wake-on-LAN, webhook notifications, Advanced tab, login logo, update check

Closes the v0.4.x chapter — NFS works end to end. Five additions:

## Wake-on-LAN (Hosts → Bound hosts)
- New core::wol module: parse any MAC form, build the 102-byte magic
  packet, broadcast it. No special capability needed (ephemeral source
  port; SO_BROADCAST). Sends to the limited broadcast (255.255.255.255)
  AND the server's own subnet broadcast (computed from advertised IP +
  detected mask) so it reaches the right VLAN.
- POST /api/hosts/:mac/wol — only fires for *bound* MACs (404 otherwise)
  so it's not an open packet sprayer.
- Bound-hosts table grows a "Wake" button with inline Waking…/Sent ✓
  state.

## Webhook notifications (Advanced tab)
- core::notify: NotifyConfig + NotifyStore (notify.json), one provider
  at a time — Slack / Discord / Teams (incoming-webhook JSON) or SMTP.
  SMTP password is persisted but redacted on GET behind a __keep__
  sentinel the UI round-trips so the secret never leaves the box.
- http-api::notify: delivery — reqwest POST for chat (provider-shaped
  bodies), lettre for SMTP (rustls, STARTTLS/implicit TLS, no plaintext).
  10s timeout; every send is best-effort.
- GET/PUT /api/notify, POST /api/notify/test.
- Fired fire-and-forget on the canonical "machine is imaging" boot event
  and on WoL — never blocks the boot path.

## UI: Advanced tab
- New nav item. Holds the webhook config card and the API reference
  block (relocated from the bottom of Settings).

## UI: login/setup logo (FleetDM treatment)
- /api/me now returns has_custom_logo + logo_rev (public bootstrap).
  The login, setup, and connection-error cards render the uploaded logo
  full-width with the "OpenPXE" wordmark dropped — matching the sidebar.

## About: update check + licenses
- "Check for updates" button → GET /api/updates/check queries the Gitea
  releases API (derived from CARGO_PKG_REPOSITORY) and compares to the
  running version. Strictly on-demand — no background polling, keeps the
  air-gapped promise.
- License card documents the MIT OR Apache-2.0 dual license with links,
  plus a note on bundled components (iPXE GPLv2/UBDL, samba, wimtools).

Deps: lettre (SMTP, rustls) + reqwest gains the json feature. Both
rustls so the static musl binary stays OpenSSL-free.

Tests: 179 passing (+notify round-trip/redaction, webhook validation,
WoL-unbound-404, WoL packet loopback, version-compare). clippy clean.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

Cargo.toml

@@ -12,7 +12,7 @@ members = [
 ]
 
 [workspace.package]
-version = "0.4.69"
+version = "0.5.0"
 edition = "2021"
 rust-version = "1.95"
 license = "MIT OR Apache-2.0"
@@ -35,7 +35,7 @@ axum = { version = "0.7", features = ["macros", "multipart", "http2"] }
 tower = "0.5"
 tower-http = { version = "0.6", features = ["fs", "trace", "cors", "limit"] }
 hyper = "1.4"
-reqwest = { version = "0.12", default-features = false, features = ["rustls-tls", "stream"] }
+reqwest = { version = "0.12", default-features = false, features = ["rustls-tls", "stream", "json"] }
 mime = "0.3"
 mime_guess = "2.0"
 
@@ -66,6 +66,11 @@ rust-embed = { version = "8.5", features = ["include-exclude"] }
 nfs3_client = { version = "0.9", features = ["tokio"] }
 nfs3_types = "0.5"
 
+# v0.5.0: SMTP for webhook notifications (Slack/Teams/Discord go over
+# plain HTTP via reqwest; email needs a real SMTP client). rustls TLS
+# to match reqwest and stay musl-static-friendly — no OpenSSL.
+lettre = { version = "0.11", default-features = false, features = ["smtp-transport", "tokio1-rustls-tls", "builder", "hostname"] }
+
 openpxe-core = { path = "crates/core" }
 openpxe-dhcp-proxy = { path = "crates/dhcp-proxy" }
 openpxe-tftp = { path = "crates/tftp" }