feat: add torch-lock remove command for complete TORCH uninstallation

Users who installed TORCH via `npm install <tarball> && npx torch-lock init`
had no built-in way to cleanly remove it. This adds a `remove` command that
detects and removes all TORCH artifacts: the torch/ directory, config files,
runtime directories (.torch/, .scheduler-memory/, task-logs/), governance
proposals, host package.json scripts, and the npm package itself.

- Add cmdRemove() in src/ops.mjs with detection, preview, confirmation, and cleanup
- Wire up `remove` command in CLI dispatcher (src/lib.mjs)
- Add TORCH_HOST_SCRIPTS constant in constants.mjs for shared script key list
- Add docs/removal.md with full manual removal instructions
- Add removal section to README.md
- Add 7 scenario tests in test/ops-remove.test.mjs

https://claude.ai/code/session_011Snrxu3iZGLtJ9pnFSajpM

package.json

@@ -68,7 +68,8 @@
     "test:ci-resilience": "node --test test/lock-acquisition-resilience.integration.test.mjs",
     "test:extended-main": "npm run test:integration:e2e && npm run test:ci-resilience",
     "torch:memory:list": "node bin/torch-lock.mjs list-memories",
-    "torch:memory:inspect": "node bin/torch-lock.mjs inspect-memory"
+    "torch:memory:inspect": "node bin/torch-lock.mjs inspect-memory",
+    "torch:remove": "node bin/torch-lock.mjs remove"
   },
   "dependencies": {
     "nostr-tools": "2.19.4",