Ingestion: Home Assistant WebSocket push path

HomeAssistantWebSocketWorker holds a persistent state_changed subscription per HA endpoint that opts in via the connector's WebSocket toggle (HaEndpointConfig.UseWebSocket): auth handshake, subscribe, ingest in real time, capped-backoff reconnect. The REST poll worker skips WS endpoints so each is served once. HaWebSocketProtocol holds the pure handshake/parse logic. Verified by 11 protocol unit tests + a live integration test against an in-process fake HA server. CLAUDE.md updated.

Claude-Session: https://claude.ai/code/session_01Kib2MniVFbD95fkgLgBBnB

CLAUDE.md

@@ -6,7 +6,7 @@ This file provides guidance to Claude Code (claude.ai/code) when working with co
 
 MeterVault is a self-hosted, local-first energy & utility metering platform: it ingests meter data from Home Assistant, Tasmota and MQTT on a schedule, stores every reading timestamped and immutable, normalizes it into consumption, and turns it into cost dashboards. Energy types (electricity, water, heating oil, gas, …) and meters are **user-defined, never hardcoded**.
 
-**Status: implemented (M0–M7) + SDD §8 panels.** The full solution is built and green — five projects, ~108 tests, working Docker deploy. `docs/SDD.md` remains the design reference; the milestone map (§12) matches the git history (M0…M7 commits). The dedicated **PV/Solar** (`/solar`), **Oil/consumable** (`/consumables`) and **meter-detail** (`/meters/{id}`) views (SDD §8.4–§8.6) are implemented as read models in `Infrastructure/Dashboard` (`SolarService`, `ConsumableService`, `MeterDetailService`) — PV meters are found by `Mode == GenerationCounter` and grid/load meters by a `role` tag in `Meter.Meta` (`MeterRoles`/`MeterMeta`), so nothing is hardcoded by name. **Admin write-CRUD** (SDD §8.7) is implemented as MudBlazor inline-dialog pages: energy types, meters (+ recompute on mode/baseline change), a meter's ingest sources (meter-detail Sources tab), tariffs, cost categories + members, and connectors (`ingestion_endpoint`, secrets by env-var reference only). `/admin/settings` is a read-only effective-config view (settings are env-driven and reproducible, not DB-stored). **Home Assistant reading** is configured here: an HA connector (`BaseUrl` + `TokenEnv`) + an HA source (entity id) drives `HomeAssistantWorker`'s REST poll; `HaConnectionTester` powers the connector "Test connection" button. **Meter topology & flow**: `MeterLink` (a directed `from→to` edge; a downstream meter is a *subsection* of an upstream one, multi-parent allowed) drives a per-energy-type page `/energy/{id}` with a hand-rolled SVG **Sankey** (`SankeyChart.razor`, since ApexCharts has no Sankey type) computed by `FlowService` (link value = downstream consumption, split proportionally across multiple parents; unaccounted remainder → an "Other" node). Upstream meters are wired cycle-safely in the meter editor; the nav lists a link per energy type. Remaining refinements (HA WebSocket *push* — REST poll works today; commit-arbitrary-CSV-from-UI needs a meter-mapping wizard; full de-DE UI-string localization) are noted at their commits. Set `MeterVault__SeedReferenceData=true` (compose: `METERVAULT_SEED=true`) for a one-command populated demo.
+**Status: implemented (M0–M7) + SDD §8 panels.** The full solution is built and green — five projects, ~108 tests, working Docker deploy. `docs/SDD.md` remains the design reference; the milestone map (§12) matches the git history (M0…M7 commits). The dedicated **PV/Solar** (`/solar`), **Oil/consumable** (`/consumables`) and **meter-detail** (`/meters/{id}`) views (SDD §8.4–§8.6) are implemented as read models in `Infrastructure/Dashboard` (`SolarService`, `ConsumableService`, `MeterDetailService`) — PV meters are found by `Mode == GenerationCounter` and grid/load meters by a `role` tag in `Meter.Meta` (`MeterRoles`/`MeterMeta`), so nothing is hardcoded by name. **Admin write-CRUD** (SDD §8.7) is implemented as MudBlazor inline-dialog pages: energy types, meters (+ recompute on mode/baseline change), a meter's ingest sources (meter-detail Sources tab), tariffs, cost categories + members, and connectors (`ingestion_endpoint`, secrets by env-var reference only). `/admin/settings` is a read-only effective-config view (settings are env-driven and reproducible, not DB-stored). **Home Assistant reading** is configured here: an HA connector (`BaseUrl` + `TokenEnv`) + an HA source (entity id) drives `HomeAssistantWorker`'s REST poll, or — with the connector's **WebSocket push** toggle (`HaEndpointConfig.UseWebSocket`) — `HomeAssistantWebSocketWorker` holds a persistent `state_changed` subscription and ingests in real time (the poll worker skips WS endpoints, so each is served once; `HaWebSocketProtocol` is the pure, unit-tested handshake/parse logic). `HaConnectionTester` powers the connector "Test connection" button. **Meter topology & flow**: `MeterLink` (a directed `from→to` edge; a downstream meter is a *subsection* of an upstream one, multi-parent allowed) drives a per-energy-type page `/energy/{id}` with a hand-rolled SVG **Sankey** (`SankeyChart.razor`, since ApexCharts has no Sankey type) computed by `FlowService` (link value = downstream consumption, split proportionally across multiple parents; unaccounted remainder → an "Other" node). Upstream meters are wired cycle-safely in the meter editor; the nav lists a link per energy type. **CSV mapping wizard** (`/import/wizard`): upload an arbitrary CSV, map columns → meters/roles, dry-run preview, then commit as a revertible `import_batch` (the `/import` page lists batches with one-click revert). The `instant_rate` mode is normalized (`InstantRateNormalizer`: rate integrated over time, trapezoidal). Remaining refinement: full de-DE UI-string localization (data parsing is already de-DE) — noted at its commit. Set `MeterVault__SeedReferenceData=true` (compose: `METERVAULT_SEED=true`) for a one-command populated demo.
 
 ## Source of truth