Feature/events api

[mudhoney]

Migrate event data to standalone Events API service

Summary

Replaces the in-process HEK adapter and direct DB event queries with a remote
Events API client (events.helioviewer.org). Adds an event coverage timeline,
rewrites composite-image polygon rendering from raster PNGs to vector
footprints, cleans up the module system to PSR-4, and adds ~1,500 lines of
new unit tests.

Why

The legacy event pipeline pulled HEK events from MySQL via HEKAdapter,
applied solar-rotation in PHP, and emitted pre-baked polygon PNGs at ingest
time. That model was tightly coupled to a single HEK schema, did per-frame
queries when generating movies, and could not style polygons per type.
A dedicated Events API service lets the backend issue a single batched query
for all frames and receive events with already-rotated coordinates and
vector footprints.

What changed

• Events API client -- new src/Event/Api/{EventsApi,LegacyEvents,...}
  with four endpoints (legacy, range, distributions, batch). Configurable
  URL + timeout via new ini keys; defaults to production.
• Event timeline -- new src/Event/Timeline/ (Timeline, Resolution,
  MinuteCoverage + SwimLaner, AggregatedCoverage, TimeRange).
  getDataCoverage auto-routes to it when eventLayers is present;
  endpoint contract preserved.
• EventSelections -- parses legacy [AR,all,1],[FL,...] strings into
  canonical HEK>>Active Region paths.
• Composite image polygon rewrite -- replaces raster hv_poly_* PNG
  loading with ImagickDraw::polygon from event['footprint']. Per-type
  fill colors from new EVENT_COLORS const, black stroke, matches
  frontend SVG style. Marker PNGs cached by type. Drops dead
  hpc_boundcc branch, $maxPixelScale, _sortByLayeringOrder.
• Module refactor -- interface.Module.php -> ModuleInterface.php
  (PSR-4), new AbstractModule base class. No public dispatch case names
  changed; &$params -> $params everywhere.
• Movies -- single getEventsBatch call pre-fetches all frame
  timestamps before frame generation. __destruct added to close mysqli
  handles. Movie layer limit raised 3 -> 5.
• Sentry -- per-request context on Events API errors; fixes a
  double-capture bug.

Configuration

New ini keys in settings/Config.Example.ini:

events_api_url     = "https://events.helioviewer.org"
events_api_timeout = 10

Existing installations pick up the defaults automatically.

Risk

• HTTP API contract: unchanged. URLs, params, validation, response shapes
  match main for all existing endpoints.
• Visual output: screenshots/movies show per-type colored polygons with
  black outlines instead of uniform yellow. Pixel-diff regressions need
  rebaselining.
• Upstream dependency: composite images now depend on
  events.helioviewer.org for footprints. If unreachable, screenshots
  still render -- just no polygons. Silent degradation, not a hard fail.
• HEKAdapter legacy path: still alive for Module/SolarEvents.php
  endpoints (getEvents, getEventGlossary, etc.). Third-party clients on
  those endpoints are unaffected.

Test plan

• composer test passes locally
• composer test-integration passes locally
• CI passes
• Take a screenshot at a date with several event types -- confirm
  polygons render with the right per-type color and the marker is positioned
  over the polygon
• Build a short movie spanning multiple HEK event timestamps -- confirm
  events appear on each frame and rotation moves them correctly
• Hit getDataCoverage?eventLayers=[AR,all,1]&startDate=...&endDate=...
  at a minute-level range; confirm timeline JSON contains the event series
• Same endpoint at a multi-month range -- confirm AggregatedCoverage
  path returns aggregated buckets
• Hit getDataCoverage?imageLayers=[SDO,AIA,171,1,100]&startDate=...&endDate=...
  -- confirm image-layer path is unchanged
• Verify getEvents still returns the legacy HEK shape (used by older
  clients / JHelioviewer)