Add measurement release, CAPI, and event-surface readiness

[jhillbht]

Summary

Extends gads-gtm-plugin with a governed measurement workflow:

• GTM/sGTM measurement-release baselines and comparison guardrails.
• Consent-aware conversion API readiness for Google Ads, Meta, TikTok, and X.
• A novice-facing Quick Start and portable non-Claude-agent hand-off guide.
• A deployable, read-only Apify Playwright Actor that inventories authorized public DOM interaction surfaces without clicks, form submission, input values, or query strings.
• An event-surface-audit skill/command and deterministic JSON mapper that turn that inventory into a reviewable GTM/sGTM event proposal.

Why

This complements the existing GTM/MCP work: it makes the discovery-to-release path approachable for novices while preserving human review. A visible DOM control is treated as evidence, not a conversion. The workflow prefers application-owned dataLayer.push() events, uses selectors only as a fallback, requires GTM Preview evidence before publishing, and keeps consent, deduplication, and secrets controls in place for server-side delivery.

Validation

• Built the new Actor with npm ci && npm run build.
• Validated all added JSON configuration files with python3 -m json.tool.
• Ran the event-map builder against a representative DOM inventory fixture and validated its JSON output.
• Ran git diff --check.