refactor(observability): hold OTLP export settings per signal

[yordis]

• A single interval, header set, and wire format shared by all three signals cannot answer a question that was asked about one signal, so any future per-signal configuration has nowhere to land.
• Holding them per signal makes it structurally impossible to pair a credential or wire format from one source with an endpoint that came from another.
• Split out of feat(observability): honor the standard OTEL_* environment variables #12621 so that pull request can shrink to the behavior it actually adds.

Summary by CodeRabbit

• New Features

  • Added separate observability export settings for traces, metrics, and logs.
  • Each signal can now use its own protocol, headers, and export interval.
  • Added default export settings for consistent telemetry configuration.

• Bug Fixes

  • Updated trace, metric, and log delivery to use their corresponding signal-specific settings.

[macroscopeapp]

Approvability

Verdict: Approved at 55cc015

Macroscope's review found this PR approvable — This is a behavior-preserving observability configuration refactor: existing environment inputs and defaults continue to apply identically to traces, metrics, and logs, while settings are stored per signal. The runtime wiring is localized and covered by updated tests, with no new user-facing configuration or deployment surface.

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[coderabbitai]

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📥 Commits

Reviewing files that changed from the base of the PR and between d6f2913 and 55cc015.

📒 Files selected for processing (12)

• apps/server/src/bin.test.ts
• apps/server/src/cli/config.test.ts
• apps/server/src/cli/config.ts
• apps/server/src/cli/pair.ts
• apps/server/src/config.ts
• apps/server/src/environment/ServerEnvironment.test.ts
• apps/server/src/http.ts
• apps/server/src/observability/Layers/Observability.ts
• apps/server/src/server.test.ts
• apps/server/src/serverLogger.test.ts
• apps/server/src/serverLogger.ts
• packages/shared/src/observability.ts

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📝 Walkthrough

Walkthrough

The change replaces shared OTLP settings with per-signal trace, metrics, and log export configurations. Runtime exporters, server configuration, defaults, and tests now use the new SignalExport model.

Changes

Per-signal OTLP export configuration

Layer / File(s)	Summary
Signal export contract and configuration packages/shared/src/observability.ts, apps/server/src/config.ts, apps/server/src/cli/config.ts, apps/server/src/cli/pair.ts	Adds SignalExport and DEFAULT_SIGNAL_EXPORT. ServerConfig now contains separate export settings for traces, metrics, and logs.
Signal-specific runtime exporters apps/server/src/observability/Layers/Observability.ts, apps/server/src/http.ts, apps/server/src/serverLogger.ts	Trace, metrics, and log exporters read protocol, headers, and intervals from their corresponding export settings.
Configuration and runtime test migration apps/server/src/*.test.ts, apps/server/src/cli/config.test.ts, apps/server/src/environment/ServerEnvironment.test.ts	Test configurations and assertions now use the per-signal export fields and DEFAULT_SIGNAL_EXPORT.

Priority: ⬇️ Low

Estimated code review effort: 3 (Moderate) | ~25 minutes

Change: Refactor

Suggested reviewers: t3dotgg

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description explains the motivation and scope, but it does not use the required What Changed, Why, and Checklist sections. It also does not explicitly address UI Changes or mark that section as no…	Rewrite the description using the repository template. Add What Changed and Why sections, state that UI Changes are not applicable if appropriate, and complete the Checklist items.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the main change: storing OTLP export settings separately for each signal.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 1…
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

Full details: Description check

Explanation

The description explains the motivation and scope, but it does not use the required What Changed, Why, and Checklist sections. It also does not explicitly address UI Changes or mark that section as not applicable.

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[juliusmarminge]

Clean split out of #12621; traced every consumer (tracer, metrics, logger, browser-trace proxy) and each reads its own signal, tests and typecheck pass on 55cc015. Two non-blocking nits: Config.withDefault(10_000) in cli/config.ts could read DEFAULT_SIGNAL_EXPORT.exportIntervalMs so the default lives once, and the SignalExport doc comment refers to a per-signal source that only arrives in #12621.