refactor(web): remove the unread playground funnel analytics

docs/ARCHITECTURE.md

@@ -161,10 +161,9 @@ private or custom local files never reach a browser bundle.
   `rewrite-handler.js`, `streaming-api.js` — web / hosted rewrite path
 - `src/web-config.js`, `web-observability.js`, `rate-limit.js`, `security.js` —
   web rewrite serving infrastructure
-- `src/web-prompt-budget.js`, `web-rewrite-receipt.js`, `pro-monitor.js`,
-  `funnel-analytics.js` — hosted request-shaped prompt budgets, downloadable
-  audit receipts, aggregate-only Pro health monitor, and privacy-safe funnel
-  events (no request content retained)
+- `src/web-prompt-budget.js`, `web-rewrite-receipt.js`, `pro-monitor.js` —
+  hosted request-shaped prompt budgets, downloadable audit receipts, and the
+  aggregate-only Pro health monitor (no request content retained)
 - `src/entitlement.js`, `entitlement-polar.js` — server-only Pro entitlement
   (Polar license-key validation)
 

docs/operations/README.md

@@ -16,7 +16,6 @@ directory is excluded from the npm tarball (`package.json` `files`:
 | `pro-margin-decision-20260729.md` | Pro cap = 100 rewrites/month; cited from `src/web-rewrite-contract.js` |
 | `serving-engine-cost-20260725.md`, `serving-engine-deepseek-0731-correction-20260803.md` | serving-engine cost and quality measurements cited from `src/` and `.env.example` |
 | `serving-engine-gemini-3.7-flash-20260813.md` | latest engine decision: 3.7-flash allowlisted opt-in, Pro pin unchanged |
-| `multilingual-funnel-20260907.md` | funnel measurement runbook |
 | `backend-compat-kimi-gemini-agy-20260913.json` | current compatibility record for all five local CLI backends. Quota behavior, other operating systems and gemini-cli API-key mode are not covered |
 | `pay-b-binding-polar-20260729.json`, `pay-live-runtime-polar-20260729.json` | Polar checkout evidence read by `scripts/checkout-evidence-bindings.mjs` |