chore(tidy): drop dead .config/tsconfig.* files + fix monorepo type script

The `.config/` tsconfig family was leftover from the pre-monorepo
layout. After code moved to `packages/cli/src/`, the only one anyone
still calls is `.config/tsconfig.base.json` (extended by every
package-local tsconfig). The other five were unreferenced:

- `tsconfig.json` — pointed at `../src/**` that doesn't exist; broke
  `pnpm run type` with TS18003 (no inputs found).
- `tsconfig.check.json`, `tsconfig.test.json`, `tsconfig.build.json`,
  `tsconfig.external-aliases.json` — orphaned, zero call sites.

Changes:
- Delete the five dead tsconfigs.
- Re-point `packages/cli` `type` script at its own tsconfig.json
  (which extends `../../.config/tsconfig.base.json`).
- Drop the misleading "extends from .config/tsconfig.json" line and
  the dead tsconfig basenames in validate-config-paths.mts.
- Fix `socket.yml` projectIgnorePaths to the post-monorepo location
  (packages/cli/test/fixtures/...).
- Gitignore `/test/` at root so the stale pre-monorepo scaffold dir
  (stray pnpm-workspace-state-v1.json) can't reappear.

Author: jdalton

.config/tsconfig.build.json

@@ -42,6 +42,8 @@ yarn-error.log*
 **/coverage/
 **/dist/
 /external/
+# Stale pre-monorepo scaffold dirs at root — tests now live in packages/cli/test/
+/test/
 **/html/
 *.d.ts
 *.d.ts.map

.config/tsconfig.check.json

@@ -29,7 +29,7 @@
     "check-ci": "pnpm run check",
     "lint": "oxlint -c ../../.config/oxlintrc.json",
     "lint-ci": "pnpm run lint",
-    "type": "tsc -p ../../.config/tsconfig.json --noEmit",
+    "type": "tsc -p tsconfig.json --noEmit",
     "type-ci": "pnpm run type",
     "sync-checksums": "node scripts/sync-checksums.mts",
     "cover": "node --import=./scripts/load.mts scripts/cover.mts",

.config/tsconfig.external-aliases.json

@@ -1,4 +1,4 @@
 version: 2
 
 projectIgnorePaths:
-  - 'test/fixtures/commands/fix'
+  - 'packages/cli/test/fixtures/commands/fix'