1

PASS

2

None.

3

First real .ts ESM module may expose package-boundary assumptions. Under module: "NodeNext", .ts files are interpreted using Node-style package rules; a project of .ts files emits CommonJS by default unless an enclosing package.json has "type": "module" or the files use .mts. That is not a blocker for this substrate PR, but P03 should explicitly confirm the first leaf .ts module is under an ESM package boundary or use .mts. [Source: TypeScript Modules Reference] 
TypeScript

allowJs:false means .ts files cannot freely depend on existing .mjs implementation without declarations. That is acceptable for a strict migration, but P03/P04 need boundary declarations or conversion ordering so new TS does not fall into implicit-any module imports. TypeScript documents allowJs as the switch that allows JS files to be imported into a TS project, and checkJs as JS error reporting when JS is included. [Source: TypeScript TSConfig Reference] 
TypeScript

The zero-floor ratchet is intentionally strict and may reject temporary phase-local debt. Counting any/@strict-debt against frozen per-directory floors is merge-safe, but contributors must either keep every phase exit at zero or consciously update the baseline only as a reviewed migration event. This is a workflow risk, not a correctness blocker.

The bin smoke is a good early-warning signal but not a full packaging/install proof. Running both bin shims with --help, checking executable bits, and preserving bin/files gives meaningful coverage; however, packed-tarball install behavior and generated Windows .cmd launchers are still outside this smoke. npm’s bin field is what causes global installs to link or generate command wrappers, and npm’s files field controls packed package contents. [Source: npm package.json docs] 
npm Docs

noEmit:true keeps this PR safe but delays emit/runtime validation. This is appropriate for P00.5+P00+P01 because TypeScript can be used as a source type-checker without emitting JS, but later phases must still prove import specifiers, extension choices, and runtime packaging once source TS begins replacing implementation. [Source: TypeScript TSConfig Reference] 
TypeScript

4

Approved to commit and push the substrate.

Approved to open a PR for P00.5 + P00 + P01 alone. Do not bundle P03 leaf-utils into this PR; keeping the substrate separate is the right granularity.