These task depends on T231586
**Acceptance Criteria:**
[ ] Define route for /version/{id}/compare/{other}
[ ] Ensure wiring is available to wikidiff2 instance descrbied in T231586
[ ] Define route handler for compare that handles the following:
[ ] Request:
[ ] **Must support** HTTP GET **only**
[ ] Request body **must** be empty
[ ] Request headers:
[ ] **Must support** If-Modified-Since: only if the result set has changed since this date
[ ] **Must support** If-None-Match: only if the result set's etag is different from this
[ ] Response:
[ ] Response **must return** JSON
[ ] Responses JSON must have structure:
```
{
"response": {
"from": "889268680",
"to": 848883822,
"title": "Some really great title",
"diffs": [
// Structure TBD
]
}
}
```
[ ] //diffs// **To be defined**
[ ] Response headers **must contain**:
[ ] Last-Modified: last time this result set was modified
[ ] ETag: etag for this result set
[ ] Expires: far future (should be immutable)
[ ] Response Statuses
[ ] 200 - OK
[ ] 304 - no change between revisions
[ ] 404 - One or both version IDs don't exist