FE-843: Toolchain profile expansion — TS runtimes + live profile selection

[kostandinang]

Stack Context

Expands the FE-829 toolchain contract so brunch cook can build on more technologies than bun, and so the profile selection path actually works.

What?

• Data-driven profile registry (project-profile.ts) — profiles are data literals (path templates + argv template + conventions prose) compiled into the unchanged Toolchain interface. Adds node-vitest, node-test, node-jest, deno alongside bun/brunch; registry invariants pinned enumerably over every entry. Adding a runtime = one data entry.
• Live + strict selection — brunch plan --profile=<id> (validated); the emitter resolves the chain once (--profile flag ≫ spec profile ≫ architect-classified ≫ bun) and stamps the resolved id into plan.yaml on both the authored and fallback paths, so cook always reads the profile the emitter used (I130-K). resolveToolchain now throws UnknownProfileError on a typo'd id instead of silently running bun; absent stays lenient for hand-authored fixtures.
• Architect classifies the stack from spec prose — optional profile enum on the architectPlan schema (null when the spec is silent); a hallucinated id fails schema parse and rides the existing deterministic fallback. No host introspection (D160-K intact).

Why?

Before this branch both implemented profiles were TypeScript and the selection path was dead — nothing populated snapshot.profile, so every cook run silently resolved to bun, and a typo'd profile id silently defaulted rather than erroring. Adding profiles without live selection changes nothing at runtime; live selection without strictness hides real misconfiguration.

Deliberately not included (recorded in PLAN as follow-ons): a harness install verb (the cook agent scaffolds + installs per A98), fail/infra test-outcome split, brownfield drift-check at cook open, brunch detect. Outer-loop validation outstanding: a greenfield cook smoke with --profile=node-vitest as the conventions-prose oracle.

🤖 Generated with Claude Code

[kostandinang]

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Learn more

• FE-872: Install-failure classification — infra-vs-test split + honest halt reason #218
• FE-871: brunch toolchain detection — detect + plan-emitter wiring #214
• FE-867: Agent extension host — dual-mode (elicit/execute) pi-harness contract #213
• FE-864: Plan orchestrator brownfield enhancements #212
• FE-843: Toolchain profile expansion — TS runtimes + live profile selection #198 👈 (View in Graphite)
• FE-841: Embed pi as an in-process SDK to drop the external pi CLI dependency #194 : 1 other dependent PR (#211 )
• main

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[cursor]

PR Summary

Low Risk
Orchestrator/planning and CLI surface changes with broad test coverage; strict unknown-profile errors improve misconfiguration visibility rather than introducing security or data risks.

Overview
Expands cook toolchain profiles beyond bun/brunch and makes profile selection actually drive planning and execution.

Registry: project-profile.ts is refactored to a data-driven registry (PROFILE_DATA → compileProfile → unchanged Toolchain API). New profiles: node-vitest, node-test, node-jest, deno, each with path templates, test argv, and agent-facing testConventions (including scaffold/install hints where needed). parseProfileId and UnknownProfileError validate CLI/YAML ids; resolveToolchain no longer silently maps unknown ids to bun — absent profile stays lenient, unknown throws.

Selection at plan time: brunch plan gains --profile=<id> (wired through plan-runner and server CLI). emitPlanFromSnapshot resolves profile once with precedence --profile ≫ snapshot profile ≫ architect-classified ≫ bun, stamps plan.profile on success and fallback paths, and derives verification targets from the resolved toolchain.

Architect: Optional profile on the architect draft schema (enum of PROFILE_IDS or null); prompt instructs stack classification from spec prose only. Invalid/hallucinated profiles fail schema parse and trigger the existing deterministic fallback.

Docs/tests: memory/PLAN.md records FE-843 branch-complete; unit tests cover registry invariants, selection precedence, CLI parsing, and architect profile behavior.

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[kostandinang]

Follow-on work tracked in FE-864 — Orchestrator enhancements: brownfield feature delivery from spec. This branch's deferred items (structured spec-profile field, outstanding --profile=node-vitest greenfield cook smoke, install-verb / fail-infra split / brownfield drift-check / brunch detect) will be evolved there.