feat: phase 3 observability — IMS telemetry merge

Port IMS telemetry into Primora conventions:

- core.components/core.events (migration 00004 + sqlc) scoped to projects
- POST /api/v1/ingest — single or <=500-event batches via project prm_
  keys (X-Primora-Key alias), auto-registering components, permissive CORS
- Issues: fingerprint-grouped errors with count/severity/first+last seen
- Reads: events w/ filters + before-cursor, components, stats (1h/24h/7d/30d
  bucketed series + component health + totals + metric names), metric
  series (avg/p50/p95/max)
- GET .../telemetry/stream — project-scoped SSE through an in-process hub
  (buffered subs, drop-on-slow, 25s keepalives); ?api_key=/?token= auth
  for EventSource
- Telemetry page: health/issues/events/metrics/integrate tabs, live badge,
  390px-clean; demo stubs
- @primora/client SDK (createPrimoraClient: capture*/heartbeat/installAuto,
  queued keepalive flushes)
- MCP: primora_list_issues/list_events/telemetry_stats/metric_series
- IMS README deprecation note pointing here

Also fixes workspace pins to 0.3.0 — npm ci in the frontend image was
resolving the unpublished 0.2.0 spec from the registry.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

apps/backend/internal/database/db/models.go

@@ -200,6 +200,15 @@ type CoreCollection struct {
 	UpdatedAt       pgtype.Timestamptz `json:"updated_at"`
 }
 
+type CoreComponent struct {
+	ID        uuid.UUID          `json:"id"`
+	ProjectID uuid.UUID          `json:"project_id"`
+	Name      string             `json:"name"`
+	Kind      string             `json:"kind"`
+	Meta      []byte             `json:"meta"`
+	CreatedAt pgtype.Timestamptz `json:"created_at"`
+}
+
 type CoreDbConnection struct {
 	ID              uuid.UUID          `json:"id"`
 	ProjectID       uuid.UUID          `json:"project_id"`
@@ -221,6 +230,18 @@ type CoreDocument struct {
 	UpdatedAt       pgtype.Timestamptz `json:"updated_at"`
 }
 
+type CoreEvent struct {
+	ID          int64              `json:"id"`
+	ProjectID   uuid.UUID          `json:"project_id"`
+	ComponentID pgtype.UUID        `json:"component_id"`
+	Type        string             `json:"type"`
+	Severity    string             `json:"severity"`
+	Message     string             `json:"message"`
+	Payload     []byte             `json:"payload"`
+	Fingerprint string             `json:"fingerprint"`
+	Ts          pgtype.Timestamptz `json:"ts"`
+}
+
 type CoreOrganization struct {
 	ID        uuid.UUID          `json:"id"`
 	Slug      string             `json:"slug"`