chore: remove qbzd headless daemon and its client integration

qbzd was a premature daemon experiment that never shipped (gated off
behind QBZD_ENABLED, no user access). Its ratatui 0.29 dependency pinned
unicode-width =0.2.0, which conflicts with slint's annotate-snippets in a
shared workspace. Remove it entirely; it will be reimplemented from
scratch later on the clean, UI-agnostic shell.

- Delete crates/qbzd daemon crate + workspace member (drops ratatui,
  crossterm and the other qbzd-only deps from the lock).
- Delete src-tauri qbzd_discovery (mDNS) + its commands/state wiring in
  lib.rs; drop the direct mdns-sd dep (Chromecast keeps its own via
  qbz-cast).
- Delete remoteApi/remoteEvents/playbackTargetStore; neutralize
  commandRouter to local-only dispatch (isRemote/skipIfRemote are now
  always-false no-ops so the ~100 guard call-sites keep compiling).
- Strip qbzd branches from playbackService and the remote banner from
  NowPlayingBar; excise qbzd from CastPicker (Chromecast/DLNA kept).
- Remove qbzd i18n keys (5 locales), README daemon node, gitignore note.

cargo check (crates + src-tauri) and svelte-check all green.

cc

crates/qbzd/Cargo.toml

@@ -1,77 +0,0 @@
-[package]
-name = "qbzd"
-version = "0.1.9"
-edition.workspace = true
-license.workspace = true
-description = "QBZ headless music daemon for SBCs and servers"
-
-[[bin]]
-name = "qbzd"
-path = "src/main.rs"
-
-[dependencies]
-# Core crates (all Tauri-free)
-qbz-models = { path = "../qbz-models" }
-qbz-core = { path = "../qbz-core" }
-qbz-player = { path = "../qbz-player" }
-qbz-audio = { path = "../qbz-audio" }
-qbz-qobuz = { path = "../qbz-qobuz" }
-qbz-library = { path = "../qbz-library" }
-qbz-cache = { path = "../qbz-cache" }
-qbz-integrations = { path = "../qbz-integrations" }
-qconnect-app = { path = "../qconnect-app" }
-qconnect-transport-ws = { path = "../qconnect-transport-ws" }
-
-# HTTP server
-axum = { version = "0.8", features = ["ws"] }
-tower-http = { version = "0.6", features = ["cors"] }
-
-# Async
-tokio = { workspace = true }
-tokio-stream = { workspace = true }
-async-trait = { workspace = true }
-futures-util = { workspace = true }
-
-# Serialization
-serde = { workspace = true }
-serde_json = { workspace = true }
-
-# HTTP client (for status check + OAuth)
-reqwest = { workspace = true }
-
-# Config
-toml = "0.8"
-clap = { version = "4", features = ["derive"] }
-
-# Browser open + URL encoding (for OAuth login)
-open = "5"
-urlencoding = "2"
-
-# System
-dirs = "6"
-log = { workspace = true }
-env_logger = "0.11"
-sysinfo = "0.34"
-
-# mDNS discovery
-mdns-sd = "0.11"
-hostname = "0.4"
-
-# Database
-rusqlite = { version = "0.31", features = ["bundled"] }
-
-# Credentials (shared keyring with desktop app)
-keyring = { version = "3", features = ["async-secret-service", "crypto-rust"] }
-
-# UUID (for QConnect renderer reports)
-uuid = { version = "1", features = ["v4"] }
-
-# QConnect core types
-qconnect-core = { path = "../qconnect-core" }
-
-# MPRIS media controls (Linux D-Bus, headless)
-souvlaki = "0.8"
-
-# TUI wizard
-ratatui = "0.29"
-crossterm = "0.28"