fix(cli): run unit and integration tests, and every mutant, in a throwaway home

[blafourcade]

🎯 What & why

A unit or integration test that relocated only AIDD_USER_CONFIG_DIR was one mutant away from the real profile. A Stryker mutant that drops that override sends the test to ~/.config/aidd of whoever runs the mutation. The mutant is killed, because the test fails, but the file is already written. On one machine this left a test marketplace entry (/src/framework) in the real registry, and replaced the real auth.json with a test token (#831).

🛠️ How it works

• tests/helpers/throwaway-profile.ts is a global setup. It points HOME, USERPROFILE and APPDATA at a temp home, and unsets AIDD_USER_CONFIG_DIR, AIDD_TELEMETRY_DIR and XDG_CONFIG_HOME. Every route to a profile then ends in that temp home, which is removed on teardown.
• It is declared on the unit and integration projects of both vitest.workspace.ts and vitest.mutation.config.ts.
• It runs in the main process on purpose. Stryker runs vitest in worker threads, and a thread's own process.env never reaches os.homedir(). A first version with setupFiles passed in forks and still left os.homedir() on the real home under threads. The guard test caught it with --pool threads.

🧪 How to verify

• tests/helpers/throwaway-profile.unit.test.ts: every resolver (os.homedir(), resolveHomeDir(), resolveAiddConfigDir(), userConfigDir()) lands under the temp directory, and no override is set.
  • Red before the fix: /Users/<me>: expected false to be true.
  • Red with a per-file setup under --pool threads.
  • Green now in threads and in forks.
• tests/architecture/throwaway-profile-wiring.arch.test.ts: all four projects declare the setup. It was red before the wiring.
• Mutant reproduction: rewrite if (process.env.AIDD_USER_CONFIG_DIR) return to if (false) return in src/runtime/user-config-dir.ts, then run marketplace-register-framework-use-case.integration.test.ts with HOME set to a stand-in developer home.
  • Before: the stand-in home receives .config/aidd/marketplaces.json.
  • After, in threads: the mutant is killed and the stand-in home stays empty.
• A real node scripts/run-mutation.mjs tools-copilot --force passes its initial run. The real ~/.config/aidd is unchanged before and after it.

Local results on this branch:

Check	Result
typecheck, lint, knip, type honesty	pass
architecture	128 passed
unit + integration	5021 passed
e2e	297 passed
mutation, tools-copilot	score 82.2, floor 80. Real ~/.config/aidd unchanged
leftover temp homes after the run	0

⚠️ Heads-up

• The e2e project is out of scope. It spawns the built binary, which no mutant reaches, and it is not part of a mutation run.
• Comment budget: this adds one comment line under tests/. With test(cli): kill the surviving mutants of the telemetry context #815 and test(cli): kill the surviving mutants of the kernel and the runtime #819 the count reaches 2987, exactly the baseline.

🔗 Linked issue

Fixes #831

✅ I certify

• I DO CERTIFY I READ EACH LINE OF THE PULL REQUEST BECAUSE I AM A SOFTWARE ENGINEER, NOT A AI PUPPY.

🤖 Generated with Claude Code

https://claude.ai/code/session_011x4ms5qcGuZgYhCxfdHMUb