Complete skipped and TODO tests

[nam-hle]

Problem

Several test files have incomplete or skipped tests:

• errors.test.ts — it.todo("should throw error within workspace")
• workspaces-alias.test.ts — it.todo("Validate")
• log-level.test.ts — 2 skipped tests
• exclude.test.ts — 1 skipped test
• profiling-summary.test.ts — entire describe.skip(...)

Proposed Solution

Implement all TODO and skipped tests, or remove them if the scenarios are no longer relevant. Each should either:

1. Be implemented with proper assertions
2. Be removed with a comment in the PR explaining why

Checklist

• errors.test.ts — workspace error scenario
• workspaces-alias.test.ts — validation test
• log-level.test.ts — unskip and fix 2 tests
• exclude.test.ts — unskip and fix 1 test
• profiling-summary.test.ts — unskip entire suite or remove if not needed

[nam-hle]

Worked this in PR #700. The checklist had drifted since this was filed:

Already resolved (files no longer exist):

• log-level.test.ts — gone
• exclude.test.ts — gone
• profiling-summary.test.ts — gone

Done in #700:

• errors.test.ts — sub-workspace duplicate-task test implemented and passing.

Reclassified as features/decisions (not test-completion), split out:

• workspaces-alias.test.ts → feat: validate alias configuration (duplicates, collisions, missing paths) #698 — alias config validation doesn't exist yet; the test can't pass until it's added.
• workspaces-detection.test.ts → decide behavior: pnpm-workspace matching exactly one package #699 — single-package-monorepo detection needs a behavior decision first.

Leaving this open to track the two remaining todos via #698/#699; can close once both land. (The many skipIf(isWindows) suites are #420, not this issue.)

[nam-hle]

All items resolved:

• errors.test.ts — sub-workspace duplicate-task test implemented (test: complete sub-workspace duplicate-task test (#416) #700).
• workspaces-alias.test.ts — the alias-validation it.todo is now a real test, unblocked by alias validation (feat: validate alias configuration (duplicates, collisions, missing paths) #698 / feat: validate alias config keys against known workspaces #701).
• workspaces-detection.test.ts — the single-workspace it.todo is now a real test, unblocked by the root-match detection fix (decide behavior: pnpm-workspace matching exactly one package #699 / fix: ignore workspace pattern matching the project root #702).
• log-level.test.ts, exclude.test.ts, profiling-summary.test.ts — these files no longer exist; their cases were resolved or removed earlier.

No it.todo or skipped tests tied to this issue remain. (Windows skipIf suites are tracked separately in #420.)