Fix startup/reload hangs, restore lost actions, add HA-parity feature…

[Ghawken]

…s (2025.2.2)

Addresses the failure cascade reported in #16 and a series of related defects found reviewing the 2025.2.1 release.

== Blocking network I/O on the dispatch thread (config UI freeze, #16) == The plugin's main thread — which also services every Indigo config dialog — was spending minutes in serial, sometimes unbounded, connect timeouts to offline players (verified by process sampling: 100% of samples blocked in socket connect()). The config screen could not open at all.

• New is_host_reachable() 2s TCP probe; deviceStartComm now defers unreachable players immediately (device shows "offline" error state) instead of stalling ~40s each, and a background retry loop (runConcurrentThread, previously commented out entirely) re-starts them automatically when the network returns.
• Removed the redundant 2x discover(timeout=5) sweeps per device; reuse startup discovery or direct SoCo(ip) — identical semantics.
• Bounded every unbounded HTTP call on hot paths: SOAPSend requests.post (was infinite connect timeout), initZones /status/zp, getModelName, rootZPIP status fetch.
• Startup skips playlists/favorites load when the reference player is unreachable.
• deviceStopComm: network unsubscribe only if the player answers a 1s probe; otherwise cancel local auto-renew. Offline players previously blocked plugin stop until Indigo force-killed it on reload.

== ZGT storm during announcements (#16) ==
Every zone change during an announcement walked all players with 5s fetches, melting down flaky networks (UPNP 1001, 20s read timeouts, "Host is down" on healthy speakers).

• 3s debounce on refresh_group_topology_after_plugin_zone_change (only once the cache has first populated, so fast startup isn't starved).
• 1s reachability probe + 30s negative cache per player in the ZGT walk.
• Fixed "list.remove(x): x not in list" crash in the initZones error path.
• "coord_dev missing" for players with no Indigo device now warns once per IP, then logs at debug.

== State-list sync ("state key Grouped not defined") == Devices created before Grouped/GROUP_* were added to Devices.xml kept a stale server state list; three duplicated code blocks tried to "create" states via updateStateOnServer (impossible) and errored on every start.

• initialize_custom_states now calls stateListOrDisplayStateIdChanged() to resync from Devices.xml and returns a refreshed device; all callers updated; duplicated broken blocks removed.
• Fixed startup summary reading nonexistent "GROUP_Grouped" state.
• Guarded soco.discover() returning None in startup.

== Routed-subnet support (players on a different VLAN) ==

• find_sonos_interface_ip: when no local interface sits on the configured Sonos subnet, resolve the routed source IP via the OS routing table — announcements and eventing now work across routed VLANs instead of erroring "No interface found on target Sonos subnet".
• getSoCoDeviceByIP / get_soco_device: direct SoCo(ip) instead of multicast discovery sweeps that can never cross a router ("No SoCo devices discovered" spam eliminated).

== Restored lost/broken actions (all fell through to "Unknown or
unsupported action" or crashed) ==

• ZP_RT_FavStation (RadioTime favourite stations — also used by alarms).
• Bass, Treble (had no handler anywhere), Night Mode, Play Queue, Sleep Timer, TV input, Dump URI.
• Pandora Thumbs Up/Down (actionPandoraThumbs method was missing).
• Test SiriusXM Channel (malformed Actions.xml entry + missing callback).
• Fixed dispatch-table signature mismatches: handleAction_ZP_SiriusXM (missing props — crashed on use) and handleAction_Q_Crossfade (arity).
• Fixed py2 remnant urllib.unquote -> urllib.parse.unquote (crashed favourites playback).
• Favourites router: x-sonosapi-hls: is generic HLS (Sonos Radio HD, Apple Music radio, ...) — only route to SiriusXM when the URI carries channel-linear:; other HLS/http favourites play via the generic URI+DIDL path. Removed stray early return when mode was empty.
• SiriusXM handler accepts the GUID from favourite URI fragments.

== New HA-parity features ==

• Equalizer actions: Speech Enhancement, Audio Delay (lip-sync 0-5), Surround on/off, Surround Level (TV/Music, -15..15), Music Playback Full Volume — RenderingControl SetEQ, mirroring Home Assistant/SoCo.
• Native Sonos alarm management: new action lists household alarms live and enables/disables/toggles them (optional volume override).

== Cleanup ==

• Removed both dead duplicate old_deviceStartComm methods (349 lines).
• Removed invalid block from Actions.xml.
• Downgraded routine warnings (ready-probe, cache misses) to debug.
• Misc log-prefix corrections.

Fixes #16

[Ghawken]

Pushed 9ed3dfb (v2025.2.3) to this branch: production testing surfaced that a single offline player could still stall the plugin (Indigo logged timeout waiting for plugin response ... CalcDeviceFunc). SoCo's .uid/.group/.is_coordinator on a cold instance poll ZoneGroupState against the player's own IP — a full network timeout per access in several per-player hot loops. Now resolved via a cached/probe-gated safe_uid() (falls back to the Indigo device's stored ZP_LocalUID), reachability gates on the group-evaluation and topology-dump loops, and capping soco.config.REQUEST_TIMEOUT at 5s (default 20s).