docs(internal): correct the Layout block against the real src/ tree

[myselfsiddharth]

Summary

Audit of docs/README-internal.md after the npm publish (#185), checking for staleness.

The publication claims were fine — this file's Quick Start is the contributor one (git clone + npm run ci), which publishing does not affect. It makes no npx or registry claims at all.

The Layout block was not fine. It listed six src/ packages:

src/testbed|recorder|compiler|runner|cache|metrics/

ls src/ shows nine directories plus src/cli.ts. Missing: intent/ (#124), session/ (#98 / SC-05), shared/ (#74), and the paragent binary — all landed after the block was written.

That matters more than a typo: a new agent orienting from this file would not learn that the consent gate or the intent resolver exist, and orienting new agents is the one job this section has. Regrouped to match architecture.md's framing — the binary, seven pipeline packages in dataflow order, then the two leaves that are not stages.

Also drops "Content is unchanged" from the header note, which this commit makes false, and records the correction under Open questions so the move-provenance claim stays honest.

Test plan

• Layout block matches ls -d src/*/ and ls src/*.ts exactly — nine directories plus src/cli.ts
• Pipeline order matches docs/architecture.md (intent → testbed → recorder → compiler → cache → runner → metrics)
• shared/ and session/ grouped as leaves, per architecture.md's "not pipeline stages"
• npm run lint:docs — clean (68 docs)
• No status, track, verdict, or number changed — verified by diff

Not changed

Two Open-questions bullets remain live and are not mine to close: the owner: B0 guess, and whether coding agents that hardcode README.md now land on the visitor page (the suggested fix there is a root AGENTS.md pointer).