chore(deps): document why ajv is a direct dep

Add a //ajv field explaining that the explicit ajv dependency exists
purely to force bun to hoist a single ajv 8.x copy at the root, since
bun won't dedupe ajv across snapshot.js / ajv-formats / ajv-errors when
eslint's transitive ajv@^6.x is also in the tree. Without it, each
8.x consumer gets its own nested copy (same version, different module
identities) and ajv-errors's vocabulary registration breaks.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: 2 people

package.json

@@ -2,6 +2,7 @@
   "name": "snapshot-sequencer",
   "version": "0.1.3",
   "license": "MIT",
+  "//ajv": "ajv 8.11.0 is a transitive dep of @snapshot-labs/snapshot.js (also used by ajv-formats and ajv-errors). Pinned at this level to force a single hoisted copy at node_modules/ajv. Without it, bun puts eslint's ajv@^6.x in the root slot and gives snapshot.js / ajv-formats / ajv-errors each their own nested 8.x copy — same version, different module identities, which breaks ajv-errors's vocabulary registration ('SyntaxError: Unexpected token :'). Drop this dep when bun supports nested overrides (oven-sh/bun#6608) or ajv-errors is replaced upstream.",
   "scripts": {
     "lint": "eslint src/ test/ --ext .ts",
     "lint:fix": "bun run lint --fix",