docs: add product surface map and minimal winning slice assumptions

[BrianCLong]

Motivation

• Establish a repo-grounded product-surface baseline and a Minimal Winning Slice (MWS) so implementation PRs can be small, measurable, and merge-safe.
• Standardize an evidence ID contract and deterministic output expectations up front to reduce schema churn and enforce traceability for Search, Ask/Answer, Evidence, Ingestion dry-run/jobs, and Report Export surfaces.
• Provide clear rollout guardrails and a repo-path map to limit blast radius and keep feature work within a single primary zone per PR.

Description

• Added docs/api/product-surfaces.md which defines surface families, the five-surface MWS, acceptance tests, the proposed EVID:<surface>:<entity-or-job>:<seq> evidence ID pattern, and a rollout sequence for v1.
• Added docs/architecture/product-surface-map.md which maps each proposed surface to concrete repo paths, documents the MWS architecture flow, and lists rollout guardrails and DoD scoring criteria.
• Updated repo_assumptions.md to record verified vs assumed paths, unknown contracts needing owner confirmation, must-not-touch files, validation commands, and owner groups for follow-on implementation work.
• All changes are documentation-only and recommend feature flags, deterministic artifacts (report.json, metrics.json, stamp.json), and conservative, additive rollouts.

Testing

• Ran pnpm exec prettier --check on the new/updated files and the check passed.
• Ran pnpm exec prettier --write to apply formatting to docs/api/product-surfaces.md, docs/architecture/product-surface-map.md, and repo_assumptions.md, and the write completed successfully.
• No code/unit tests were modified or required for this docs-only change; CI gates (lint/typecheck/tests) remain as recommended validation steps for subsequent implementation PRs.

---

Codex Task

[gemini-code-assist]

Warning

You have reached your daily quota limit. Please wait up to 24 hours and I will start processing your requests again!

[coderabbitai]

Warning

Rate limit exceeded

@BrianCLong has exceeded the limit for the number of commits that can be reviewed per hour. Please wait 19 minutes and 19 seconds before requesting another review.

Your organization is not enrolled in usage-based pricing. Contact your admin to enable usage-based pricing to continue reviews beyond the rate limit, or try again in 19 minutes and 19 seconds.

⌛ How to resolve this issue?

After the wait time has elapsed, a review can be triggered using the @coderabbitai review command as a PR comment. Alternatively, push new commits to this PR.

We recommend that you space out your commits to avoid hitting the rate limit.

🚦 How do rate limits work?

CodeRabbit enforces hourly rate limits for each developer per organization.

Our paid plans have higher rate limits than the trial, open-source and free plans. In all cases, we re-allow further reviews after a brief timeout.

Please see our FAQ for further information.

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 9ff9e5c5-98ac-4f02-9ba5-7bea4b3526ea

📥 Commits

Reviewing files that changed from the base of the PR and between e87382b and c305be9.

📒 Files selected for processing (3)

• docs/api/product-surfaces.md
• docs/architecture/product-surface-map.md
• repo_assumptions.md

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch codex/enumerate-summit-product-surfaces

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}

[chatgpt-codex-connector]

💡 Codex Review

Here are some automated review suggestions for this pull request.

Reviewed commit: a260aa2915

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[chatgpt-codex-connector]

Use existing evidence ID contract for v1 surface docs

The proposed contract switches to EVID:<...> IDs, but current repository schemas and verification gates still validate EVD-... IDs (for example docs/api/evidence.report.schema.json and docs/api/evidence.stamp.schema.json both require ^EVD-). Because this file defines the MWS contract, implementers following it will generate IDs that fail existing validation and CI checks, so the doc should either align with the enforced format or explicitly document a coordinated validator migration.

Useful? React with 👍 / 👎.

[chatgpt-codex-connector]

Exclude stamp.json from the no-timestamp deterministic set

This guidance forbids unstable timestamps in stamp.json, but the current stamp contract requires a timestamp field (createdAtIso in docs/api/evidence.stamp.schema.json) and repository guidance states timestamps are permitted in stamp artifacts. Keeping stamp.json in the blanket ban creates a direct contract conflict that will mislead follow-on implementation work into either violating schema or dropping required metadata.

Useful? React with 👍 / 👎.