Convert type-checked lib `.js` files to `.ts`

[dalberola]

Summary

Finish the type-safety track started in #28 by converting the remaining // @ts-check-annotated .js files in packages/dredd/lib to real .ts, replacing JSDoc type annotations with native TypeScript signatures.

Why now

• [P1] Incrementally type-check packages/dredd/lib (.js → typed) #28 (// @ts-check every lib file) is complete — 38/39 files are checked under strict (only lib/index.js is deferred to the ESM work in [P2] Migrate packages from CommonJS to ESM #29).
• lib/ is already mixed: 22 .ts + 39 .js. The toolchain handles it today — tsconfig is allowJs + node16 + strict, tests run via ts-node, and the recently-added lib/validation/ module (8 .ts files) built, tested, and shipped cleanly. No tooling changes are needed.
• With type-checking already done, conversion is largely mechanical: JSDoc @param {T} / @returns → real signatures, tightening any along the way. The hard part (making the code type-check) is behind us.

Scope

• Rename each // @ts-check lib/**/*.js → .ts and replace JSDoc types with native TS.
• One file (or one cohesive cluster) per PR, mirroring the [P1] Incrementally type-check packages/dredd/lib (.js → typed) #28 cadence.
• No behaviour changes and no change to the published surface: the package stays CommonJS (main: build/index.js, no "type": "module"); tsc emits CommonJS regardless of source extension, so consumers are unaffected.

Out of scope

• lib/index.js — the package entry and the only un-@ts-checked file; convert it as part of the CommonJS→ESM migration ([P2] Migrate packages from CommonJS to ESM #29), not here.
• Any runtime/dependency change.

Suggested order (bottom-up: foundation & leaves first)

Converting high-fan-in foundation modules first means their types immediately benefit every importer as those get converted. Grounded in current lib fan-in:

1. Logging cluster (highest leverage, self-contained, tiny): createConsoleLogger.js → logger.js (imported by 19 files) → reporters/reporterOutputLogger.js (10). Already grouped this way in [P1] Incrementally type-check packages/dredd/lib (.js → typed) #28.
2. Shared leaves (zero internal deps, trivial): expandTilde.js, which.js, ignorePipeErrors.js, getGoBinary.js, getProxySettings.js, hooksLog.js, compileTransactionName.js, prettifyResponse.js.
3. Self-contained mid-size: httpClient.js, readLocation.js, performRequest.js, configUtils.js, annotationToLoggerInfo.js.
4. Configuration cluster: configuration/{validateConfig,normalizeConfig,getProxySettings,applyLoggingOptions,applyConfiguration,index}.js.
5. Reporters: reporters/{BaseReporter,DotReporter,CLIReporter,…}.js then configureReporters.js.
6. Hubs last (high internal fan-out → most any leakage until neighbours are typed): Hooks.js, addHooks.js, HooksWorkerClient.js, init.js, Dredd.js, CLI.js, TransactionRunner.js.
7. index.js — last, with [P2] Migrate packages from CommonJS to ESM #29.

Acceptance criteria

• Every lib/**/*.js except index.js is converted to .ts with native types (no remaining // @ts-check pragmas in lib).
• tsc --build passes under strict; yarn lint, yarn test, smoke all green per PR.
• Published package remains CommonJS; no consumer-visible change.

Follow-on to #28. Interacts with #29 only for index.js.

[dalberola]

Batch 1 — logging cluster ✅ (#62, merged)

Converted bottom-up: createConsoleLogger.js → logger.js → reporters/reporterOutputLogger.js. createConsoleLogger's @template level-map generic is now a real type parameter, preserving the per-level call signatures and the transports.console contract.

Verified: tsc strict 0, lint, prettier, unit 772, integration 606, clean build, smoke. No behaviour or package-surface change.

Progress: lib .js 39 → 36.

Next eligible batch (recommended): the shared zero-dep leaves — expandTilde.js, which.js, ignorePipeErrors.js, getGoBinary.js, getProxySettings.js, hooksLog.js, compileTransactionName.js, prettifyResponse.js. Hubs (TransactionRunner, CLI, Dredd, init, HooksWorkerClient) stay last; index.js defers to #29.

[dalberola]

Batch 2 — zero-dependency leaf utilities ✅ (#64, merged)

Converted: expandTilde, which, ignorePipeErrors, getGoBinary, getProxySettings, hooksLog, compileTransactionName (each imports no other lib module, so fully isolated).

Verified: tsc strict 0, lint, prettier, unit 772, integration 606, clean build, smoke. No behaviour or surface change.

Progress: lib .js 36 → 29.

Next eligible batch: the small self-contained mid-size utilities — configUtils.js, annotationToLoggerInfo.js, readLocation.js, prettifyResponse.js (and then httpClient.js → performRequest.js). After that, the reporters cluster (BaseReporter first) and the configuration cluster. Hubs (TransactionRunner, CLI, Dredd, init, HooksWorkerClient) last; index.js with #29.

[dalberola]

Batch 3 merged in #66: converted 4 self-contained mid-size utils to native .ts — configUtils, annotationToLoggerInfo, readLocation, prettifyResponse. JSDoc @typedefs became TS interfaces; casts became as. No behaviour change.

Notably, this is the first batch landing with the typescript-eslint lint gate active (#63/#65 merged first, deliberately, so conversions don't keep shrinking lint coverage).

lib/ now 25 .js / 28 .ts. Next: httpClient → performRequest (the remaining group-3 self-contained units), then the configuration and reporters clusters, hubs last.