chore(deps): fix the jsonschema generator go.mod - #412

schema-validation fails on every other open PR while this one is unmerged, because internal/jsonschema cannot resolve against current main.

Reproduced on a clean main checkout:

$ cd internal/jsonschema && go test ./...
go: updates to go.mod needed; to update it:
	go mod tidy

Currently red for that reason on #419, #420 and #421. This PR is the only open one where schema-validation passes, and its diff matches local go mod tidy -diff output, so it appears to be the complete fix. It is still marked as a draft.

The failure recurs structurally rather than by accident: #389 was the same fix in June. The nested internal/jsonschema module drifts whenever the outer module's dependencies move, and nothing keeps the two in step, so a Dependabot bump to the outer module leaves the nested one stale. Two options for a follow-up, if wanted:

• have Dependabot track internal/jsonschema directly
• add a CI step running go mod tidy -diff in that directory, failing with a pointer to the fix rather than a bare updates to go.mod needed

Written by AI: claude-sonnet-5