Feat/compt 77 dynamic scheduling error handling

[saadmoumou]

Summary

• What does this PR change?

Why

• Why is this change needed?

Checklist

• Added/updated tests (if behavior changed)
• npm run lint passes
• npm run typecheck passes
• npm test passes
• npm run build passes
• Added a changeset (npx changeset) if this affects consumers

Notes

• Anything reviewers should pay attention to?

[Copilot]

Pull request overview

Adds a lightweight in-memory scheduler service (interval/timeout/cron) with concurrency guarding and configurable error handling, and updates build/lint tooling to support the new package shape.

Changes:

• Introduces SchedulerService + IScheduler contract, along with DuplicateJobError.
• Adds Jest coverage for scheduler behavior (timers, concurrency guard, error handling, status).
• Updates TypeScript build/lint configs and regenerates the lockfile for the new dependency set.

Reviewed changes

Copilot reviewed 11 out of 12 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tsconfig.eslint.json	Expands ESLint TS project include patterns (now includes *.mjs).
tsconfig.build.json	Switches build output to CommonJS/Node resolution and narrows build include list to scheduler-related files.
src/services/scheduler.service.ts	Implements the scheduler registry, execution guard, status reporting, and error callback handling.
src/services/scheduler.service.spec.ts	Adds unit tests for scheduling, unscheduling, rescheduling, concurrency, and error behavior.
src/interfaces/scheduler.interface.ts	Defines the public scheduler interface and discriminated-union timing types.
src/index.ts	Updates public exports to expose the scheduler service/types and the error type.
src/errors/duplicate-job.error.ts	Adds a dedicated error type for duplicate job registration.
src/errors/duplicate-job.error.spec.ts	Adds tests for the error type behavior.
package-lock.json	Updates lockfile to reflect new package name/version and dependency set.
lint-staged.config.js	Switches lint-staged config export style to CommonJS.
eslint.config.mjs	Updates ESLint flat config ignores, TypeScript project wiring, and rule set.
eslint.config.js	Removes the previous ESLint config file.

[Copilot]

tsconfig.eslint.json includes *.js/*.mjs but does not enable compilerOptions.allowJs. Since ESLint is configured with parserOptions.project, TypeScript will try to build a program from this config and will error on included JS/MJS files. Remove JS/MJS from include (keep it TS-only), or enable allowJs (and optionally checkJs: false) in this tsconfig.

Suggested change

	"include": ["src/**/*.ts", "test/**/*.ts", "*.ts", "*.js", "*.mjs"],
	"include": ["src/**/*.ts", "test/**/*.ts", "*.ts"],

[Copilot]

SchedulerService imports CronJob from the cron package, but cron is not declared in package.json dependencies/peerDependencies. This will break compilation/runtime for consumers unless cron is added as a runtime dependency (or the implementation is changed to avoid it).

[Copilot]

The SchedulerService constructor takes a plain options object. When instantiated via Nest DI, Nest will try to resolve this parameter as a provider (design type is Object) and fail. Consider removing the constructor param, or injecting options via an explicit injection token (@Inject(...) + @Optional()) provided by a module forRoot/forRootAsync factory.

Suggested change

	private readonly onJobError: (name: string, error: unknown) => void;
	constructor(options: SchedulerModuleOptions = {}) {
	this.onJobError =
	options.onJobError ??
	((name, error) => this.logger.error(`Job '${name}' threw an error`, error));
	}
	private readonly onJobError: (name: string, error: unknown) => void = (
	name,
	error,
	) => this.logger.error(`Job '${name}' threw an error`, error);

[Copilot]

reschedule() builds newJob via { ...entry.job, ...newTiming }, which retains the previous timing key(s). Rescheduling from one timing type to another can produce a job object with multiple timing properties (e.g. both interval and cron), violating the discriminated-union contract and potentially leading to ambiguous behavior. Reconstruct the job from { name, handler, ...newTiming } (and avoid the as ScheduledJob cast).

[Copilot]

The default onJobError implementation passes the caught error object as the second argument to Logger.error, which is treated as the stack/trace string. This often results in unhelpful output like [object Object] for non-Error values and can drop stack traces. Consider normalizing error to a stack string when it is an Error, otherwise String(error).

Suggested change

	((name, error) => this.logger.error(`Job '${name}' threw an error`, error));
	}
	((name, error) =>
	this.logger.error(
	`Job '${name}' threw an error`,
	this.formatJobError(error),
	));
	}
	private formatJobError(error: unknown): string {
	if (error instanceof Error) {
	return error.stack ?? error.message;
	}
	return String(error);
	}