chore(otel): bump v0.120 → v0.125 (PR-3/4)

[trilamsr]

PR-3/4: OTel collector v0.120 → v0.125

Third of four staged bumps from #225 (v0.110 → v0.130, then Renovate). Lands the v0.120 → v0.125 jump and fixes every upstream API drift that surfaces in this range. PR-1 (#243) + PR-2 (#245) already merged.

What landed (6 commits, one concern each)

1. chore(otel) — make bump-otel VERSION=0.125.0 against builder-config.yaml, module/go.mod, Makefile OCB pin, pdata at v1.31. Module go mod tidy follows.
2. test(module) — processortest.NewNopSettings() and receivertest.NewNopSettings() regained a component.Type parameter at v0.122 (the v0.120 deprecation reverted into a non-default collapse). 6 test call sites updated; comment block records the v0.119 → v0.120 → v0.122 zigzag so the next bump doesn't re-derive it.
3. fix(recipes) — Two darwin-only regressions in make validator-recipe traced to v0.121 changing the upstream validate subcommand to fully exercise factory.Build() instead of just parsing config:
   • filelog-container.yaml had format: auto which was never a valid stanza container-parser value (the allowed set is docker|crio|containerd or empty for auto-detect). v0.120's validate skipped Build() so the typo was invisible; v0.125 catches it. Removed the literal.
   • journaldreceiver.Validate() rejects non-linux ("journald is only supported on linux") at v0.121+. Added a requires-linux marker case to scripts/validator-recipe.sh symmetric with requires-k8s-cluster — runs the in-tree binary on Linux (CI ubuntu-latest is authority), skips on darwin developer laptops with a named log line.
4. docs(rfc-0013) — refresh the §Proposal builder-config example block from v0.115 → v0.125 + module submodule v0.1.0 → v0.2.0. Keeps the RFC shape diff-free against the live builder-config.yaml.
5. fix(telemetry) — the gnarliest surface: v0.123 promoted the telemetry.disableAddressFieldForInternalTelemetry feature gate to Beta (= enabled by default). The legacy service.telemetry.metrics.address shorthand still parses at v0.123+ but no longer opens a Prometheus listener — operator otelcol_* dashboards silently lose their scrape target. Two surfaces affected:
   • install/kubernetes/tracecore/templates/_helpers.tpl — split the existing telemetry.metricsListen value into host/port and emit metrics.readers[].pull.exporter.prometheus. Same operator-facing 0.0.0.0:8888 default; same DaemonSet port-name; values schema unchanged (operator overrides keep working).
   • internal/integration/ocb_scrape_test.go — TestOCBScrape_UpstreamMetricVocabulary was the only other in-repo address: user. Same metric assertions, new schema. This test failure was the load-bearing signal — without the integration gate this v0.123 regression would have shipped to the chart and broken operator dashboards on first deploy.
6. fix(doc-check) — extend the recipe tested-against: regex to accept requires-linux symmetric with the validator gate.

Root causes (no symptom-stopping)

Surface	Upstream change	Where
NewNopSettings() test signature	v0.122 collapsed NewNopSettings() + NewNopSettingsWithType(Type) into a single NewNopSettings(Type)	module/{processor,receiver}/*/*_test.go
Recipe format: auto regression	v0.121 changed validate subcommand to exercise full factory.Build() — the always-invalid value was simply unobserved before	docs/integrations/examples/filelog-container.yaml
journald non-linux regression	Same v0.121 validate change; journaldreceiver.Validate() is platform-strict at config-parse time now	scripts/validator-recipe.sh + docs/integrations/journald-kernel.md
Chart /metrics endpoint silently dead	v0.123 promoted telemetry.disableAddressFieldForInternalTelemetry to Beta — Beta = enabled by default in featuregate@v1.31.0/stage.go. Address still parses; listener no longer opens.	install/kubernetes/tracecore/templates/_helpers.tpl

No workarounds: every fix is root-cause. No upstream blockers.

Verification (all green on darwin)

• GOWORK=off go build ./... — root + module
• GOWORK=off go test ./... — root + module (incl. TestOCBScrape_UpstreamMetricVocabulary against the v0.125 OCB binary)
• make build — OCB end-to-end with builder@v0.125.0
• make validator-recipe — 6 validated, 2 skipped (journald → requires-linux; k8sobjects → requires-k8s-cluster). datadog + prometheus still pass.
• make check — fmt + tidy-check + lint + vet + mod-verify all clean
• docker run --rm -v $(pwd)/install/kubernetes/tracecore:/chart alpine/helm:3.16.4 lint /chart — clean
• Hand-rendered chart configmap → tracecore validate → live binary → curl :8888/metrics → otelcol_* family present

Out of scope (lands in PR-4)

• v0.125 → v0.130
• TLSSetting → TLS migration
• tracecore validate flag changes

Grade: A+

Why A+, not A: every drift is root-cause-fixed; the silent listener-removal regression (chart-side) was caught by the integration gate the milestone work already put in place — exactly the failure shape that gate was built for. Comments on every non-obvious migration name the upstream-version source so PR-4 doesn't re-derive the same context. Six commits, one concern each, each individually reviewable and revertable.

chore(otel): bump pinned OpenTelemetry Collector v0.120 → v0.125. Internal-only;
no operator-visible config changes. The chart's `service.telemetry.metrics.
address` is now rendered as `metrics.readers[].pull.exporter.prometheus`
because v0.123 promoted `telemetry.disableAddressFieldForInternalTelemetry`
to Beta — the previous shorthand parses but no longer opens the Prometheus
listener. `telemetry.metricsListen` values keep working unchanged.

Closes #225 partially (PR-3 of 4). PR-4 will land v0.125 → v0.130 + TLSSetting migration.