feat(api): CL0UD capability probe + a11y/HAR evidence + worker scale toggle

- cl0ud client: contract-first probe of documented GET /capabilities/:id,
  status connected/denied/unavailable/disabled surfaced in /health;
  CL0UD_REQUIRED=true = fail-closed 503; full policy-decisions gated on
  CL0UD B-4/ADR-0031 (deliberately not simulated)
- capture depth: accessibility tree + condensed HAR as evidence kinds
  (null = explicit evidence gap)
- CAPTURE_WORKER=on/off for separate-scale deployments
- 34/34 tests

packages/config/src/index.ts

@@ -17,6 +17,10 @@ export const envSchema = z.object({
   N0D_BASE_URL: z.string().url().optional(),
   CRAWL_TIMEOUT_MS: z.coerce.number().default(30000),
   MAX_REGISTRY_PAGES: z.coerce.number().default(1000),
+  CAPTURE_WORKER: z.enum(["on", "off"]).default("on"),
+  CL0UD_API_TOKEN: z.string().optional(),
+  CL0UD_REQUIRED: z.enum(["true", "false"]).default("false"),
+  CL0UD_PROBE_INTERVAL_MS: z.coerce.number().default(300000),
 });
 
 export type Env = z.infer<typeof envSchema>;