SDD §8 panels (PV/oil/meter-detail) + fix reference-data-in-Docker

Complete the SDD §8 dashboard views that were deferred at the M5 boundary,
and fix a shipping bug that left the Docker demo empty.

Bug: "Load reference data" created meters/tank/tariffs but imported zero
readings in Docker. Root cause: sampledata/ was excluded by .dockerignore and
never copied into the build stage, so the App csproj's linked Content glob
resolved to nothing at publish time; ReferenceDataImporter then silently
skipped the missing CSVs after already writing its marker meter, leaving the
DB permanently "loaded" but empty.
  - .dockerignore: stop excluding sampledata/
  - Dockerfile: COPY sampledata/ into the build stage
  - ReferenceDataImporter: fail-fast (validate CSVs exist before the marker
    meter) and throw instead of silently skipping a missing file
  - Program.cs + MeterVaultOptions: opt-in MeterVault__SeedReferenceData
    (compose METERVAULT_SEED=true) for a one-command populated demo

New SDD §8 panels (read models in Infrastructure/Dashboard, Blazor pages):
  - §8.4 Solar/PV (/solar): generation from GenerationCounter meters;
    self-consumption / autarky % / self-consumption % / savings derived from
    meters tagged total_load & grid_import via Meter.Meta role config
    (MeterRoles/MeterMeta) — nothing hardcoded by name.
  - §8.5 Oil/consumable (/consumables): tank level (cm→L calibrated), fill
    gauge, deliveries log, burner runtime, effective L/h (fixed/empirical),
    forecast-to-empty, tariff cost, monthly series.
  - §8.6 Meter detail (/meters/{id}): raw readings, normalized consumption,
    source status, tariff timeline, events, measured-vs-estimated markers.
  - Reusable SeriesChart component; nav links; Meters list rows link to detail.

Tests: MeterMetaTests (Core, +10); DashboardRenderTests extended to assert the
three panel services compute real figures and the new routes render (108 total,
all green). Live-verified in Docker: seed imports 302 readings / 347 consumption
rows; panels render (generation 16,481 kWh, oil 3,967 L) cross-checking the DB.

Claude-Session: https://claude.ai/code/session_01Lz2RqAsnQhetqWNoCDfexK

README.md

@@ -22,7 +22,10 @@ full design.
   per meter; **cost categories** decoupled from energy types; meterless manual costs.
 - **Continuous aggregates** (daily/monthly/yearly, local timezone) so dashboards never scan raw.
 - **Dashboard**: cost KPIs with period-over-period deltas, "what costs most", a "what cost more/
-  less" difference view, trends, meter list, one-click reference-data load, CSV dry-run.
+  less" difference view, trends, a **PV/Solar panel** (generation, self-consumption, autarky %,
+  savings), an **oil/consumable panel** (tank gauge, deliveries, burner runtime, effective L/h,
+  forecast-to-empty) and a **per-meter detail view** (raw readings, consumption, sources, tariff
+  timeline, events), one-click reference-data load, CSV dry-run.
 - **REST API + OpenAPI/Swagger**, API-key auth, reverse-proxy trust (Authelia/Traefik).
 - **JSON config export/import** for portability; Docker Compose + multi-arch image.
 
@@ -31,6 +34,7 @@ full design.
 ```bash
 docker compose -f deploy/docker-compose.yml up -d
 # open http://localhost:8080  → Import → "Load reference data" for a populated demo
+# ...or start pre-populated:  METERVAULT_SEED=true docker compose -f deploy/docker-compose.yml up -d
 # API docs at http://localhost:8080/swagger
 ```
 
@@ -44,6 +48,7 @@ Configuration is via environment variables (`Section__Key` double-underscore map
 | `MeterVault__AllowAnonymousApi` | `true` to open the REST API without a key (trusted LAN only) |
 | `MeterVault__ReverseProxyTrust` | `true` to honour `X-Forwarded-User` behind an auth proxy |
 | `MeterVault__EnableLiveIngestion` | `false` to disable the MQTT/HA workers |
+| `MeterVault__SeedReferenceData` | `true` to load the bundled demo dataset on first start (idempotent) |
 
 The REST API is **closed by default**: with no `ApiKeys` configured and `AllowAnonymousApi` off, it
 returns 401. Set at least one API key (or open it explicitly for a trusted network).