Align examples with the shared v0.20.1 release

[jilio]

Align both observability examples with the published root and OpenTelemetry v0.20.1 modules, completing the shared-release dependency alignment after PR #60. The four manifest/checksum files were updated through ordinary verified module downloads after the nested tags became available.

Validation:

• Both examples passed standalone formatting, build, vet, normal tests and race tests on their minimum Go version, 1.25.12; both selected root and OpenTelemetry v0.20.1.
• All six workspace modules passed formatting, build, vet, normal tests and race tests, followed by the replication process-loss smoke test.
• Core/state coverage remains 100.0%; SQLite coverage is 97.6%.

[claude]

Review

This is a clean, minimal dependency-alignment PR — only go.mod/go.sum in the two examples/observability* modules are touched, bumping github.com/jilio/ebu and github.com/jilio/ebu/otel from v0.20.0 → v0.20.1. No application/source code changes.

Checksum consistency (verified by inspection):

• github.com/jilio/ebu go.mod hash is unchanged between v0.20.0/v0.20.1 (HudFk9G...), consistent with the root module's go.mod not changing in the patch release.
• github.com/jilio/ebu/otel go.mod hash did change (1jHZ12... → Jqg/Ss...), which matches otel/go.mod in this tree now requiring the root module at v0.20.1 — i.e. the otel submodule's own dependency was bumped for the release. The two example modules and the workspace's own otel/go.mod are all consistent with each other.
• Both go.mod requires and matching go.sum h1:/go.mod entries were updated together in both examples — no stale/mismatched lines.

Code quality: N/A — no Go source changed, so go fmt has nothing to do here. The diff looks like the direct output of go get github.com/jilio/ebu@v0.20.1 github.com/jilio/ebu/otel@v0.20.1 (or equivalent), not hand-edited, which is the right way to do this kind of bump.

Bugs/correctness: None spotted — this is a pure patch-version bump of an in-repo dependency, and the two examples were bumped in lockstep so they won't drift from each other or from otel/go.mod.

Performance: N/A.

Security: Low risk — patch bump of first-party modules from the same repo, checksums recorded via ordinary go get/go mod verified downloads (per PR description), so GOSUMDB verification applies normally. Nothing here introduces a new dependency or widens any version constraint beyond patch level.

Test coverage: N/A for this diff (examples aren't part of core coverage). PR description states core/state remains 100% and SQLite 97.6%, and that both examples were built/vet/tested (incl. race) standalone plus as part of the full workspace — that's good validation for a dependency bump like this. I wasn't able to independently re-run go build/go test/go vet in this review environment (sandboxed, no shell execution), so I'm relying on the PR description's validation notes plus the static consistency checks above; the repo's test.yml CI should confirm this on merge.

Overall: straightforward, well-scoped, and internally consistent. No changes requested.