test(server): skills discovery asserts unrealpath'd TMPDIR paths — deterministic failure on macOS (/var → /private/var)

apps/server/src/provider/Layers/CursorProvider.test.ts — "Cursor skills > discovers recursive project skills with project precedence" fails deterministically on macOS.

Introduced by #9180 (workspace-skill discovery): discovery canonicalizes every skill path with fs.realpathSync, but the fixture builds its expectations from os.tmpdir() without canonicalizing. On macOS $TMPDIR sits under /var, which is a symlink to /private/var, so the expected strings can never equal the received ones:

expected: /var/folders/…/T/cursor-skills-workspace-…/.cursor/skills/internal/SKILL.md
received: /private/var/folders/…/T/cursor-skills-workspace-…/.cursor/skills/internal/SKILL.md

(3 of 3 project-scope entries differ exactly this way; the test is 1 failure / 24 passes in the file, reproducible on every run.)

Product code looks correct — canonicalizing is deliberate (it matches Node's own import.meta.url behavior for ESM) and keeps discovery results stable across symlinked install locations. Linux CI is unaffected (/tmp is not a symlink there), which is why this only shows up running the suite locally on macOS.

Suggested fix: build the fixture's expected paths from fs.realpathSync(workspaceRoot) (same class as the entrypoint.test.ts symlink case, which has the same macOS-only failure mode).

Open apps/server/src/provider/Layers/CursorProvider.test.ts and locate “Cursor skills > discovers recursive project skills with project precedence.” Compare the fixture’s expected paths with the discovery output, then run the test file on macOS; done means the project-scope expectations use canonical paths and the test passes.