OTel int64 serialization fixed; monitors get metadata filter

What's Changed

Features

• feat(evals): emit code eval dispatch duration distribution metric by @wochinge in https://github.com/langfuse/langfuse/pull/15071
• feat(monitors): allow metadata filter in monitor queries by @marksalpeter in https://github.com/langfuse/langfuse/pull/15033
• feat(otel): tag x-langfuse-ingestion-version header on OTel API spans by @maxdeichmann in https://github.com/langfuse/langfuse/pull/15076
• feat(filters): default root obs filter on for app roots by @nimarb in https://github.com/langfuse/langfuse/pull/15066
• feat(mcp,monitors): Add listMonitors and getMonitor tools by @bezbac in https://github.com/langfuse/langfuse/pull/15065
• feat(evals): remove propagation filter warning popup by @marliessophie in https://github.com/langfuse/langfuse/pull/15101
• feat(seeder): add support-agent scenario — handcrafted demo-grade agent trace by @nkabardin in https://github.com/langfuse/langfuse/pull/14985
• feat(charts): add hideXAxisLabels option to improve readability by @marliessophie in https://github.com/langfuse/langfuse/pull/15027
• feat(auth): add NEXTAUTH_COOKIE_NAME_SUFFIX to namespace auth cookies across instances by @maxdeichmann in https://github.com/langfuse/langfuse/pull/15094

Fixes

• fix(otel): serialize int64 fields as strings, not protobufjs Long internals by @he-yufeng in https://github.com/langfuse/langfuse/pull/13342
• fix(agent): Add gradient animation to loading state by @bezbac in https://github.com/langfuse/langfuse/pull/15064
• fix(seeder): make the demo seeder import-safe outside a monorepo checkout by @maxdeichmann in https://github.com/langfuse/langfuse/pull/15070
• fix(pricing): price normalized Gemini reasoning tokens by @hassiebp in https://github.com/langfuse/langfuse/pull/15082
• fix(mcp): Add user agent to mcp spans by @bezbac in https://github.com/langfuse/langfuse/pull/15078
• fix(worker): stream core data S3 exports with keyset pagination by @Steffen911 in https://github.com/langfuse/langfuse/pull/15083
• fix(llm): allow custom OpenAI provider options by @hassiebp in https://github.com/langfuse/langfuse/pull/15085
• fix(agent): Make user aware of screen context by @bezbac in https://github.com/langfuse/langfuse/pull/15079
• fix(otel): add validation for experiment-item-version by @marliessophie in https://github.com/langfuse/langfuse/pull/15062
• fix(tests): align eval rule limit tests with 500 cap by @LysanderKie in https://github.com/langfuse/langfuse/pull/15108
• fix(web): fall back when crypto.randomUUID is unavailable on non-secure origins (LFE-10858) by @nkabardin in https://github.com/langfuse/langfuse/pull/15058
• fix(mcp): Instrument more auth level fields by @bezbac in https://github.com/langfuse/langfuse/pull/15111
• fix(codex): guard trap against unbound tmp_dir in ensure_migrate_binary by @marksalpeter in https://github.com/langfuse/langfuse/pull/15112
• fix(auth): route next-auth logging through structured logger by @Steffen911 in https://github.com/langfuse/langfuse/pull/15096
• fix(preview): resolve preview-comment action from base, build from PR head by @maxdeichmann in https://github.com/langfuse/langfuse/pull/15075
• fix(sessions): bound trace-card I/O in the session detail view (LFE-10958) by @nkabardin in https://github.com/langfuse/langfuse/pull/15124
• fix(trace): keep tree and timeline layouts readable on extremely deep traces (LFE-10959) by @nkabardin in https://github.com/langfuse/langfuse/pull/15123

Chores

• chore: preview write access by @maxdeichmann in https://github.com/langfuse/langfuse/pull/15060
• chore(agent): run model price audit daily by @hassiebp in https://github.com/langfuse/langfuse/pull/15067
• refactor(llm): make AI SDK the sole completion runtime by @hassiebp in https://github.com/langfuse/langfuse/pull/14979
• chore(worker): Enable knip dep checking & remove unused deps by @bezbac in https://github.com/langfuse/langfuse/pull/15028
• chore(unstable-llm-api): increase max eval rule count to 500 by @hassiebp in https://github.com/langfuse/langfuse/pull/15103
• refactor(llm): use native AI SDK errors by @hassiebp in https://github.com/langfuse/langfuse/pull/15091
• docs(contributing): add CLA license check troubleshooting steps by @marksalpeter in https://github.com/langfuse/langfuse/pull/15090
• chore(events): extract shared event row-selection planning by @sumerman in https://github.com/langfuse/langfuse/pull/14974
• chore(preview): add web/worker log commands to the preview PR comment by @maxdeichmann in https://github.com/langfuse/langfuse/pull/15127

New Contributors

• @he-yufeng made their first contribution in https://github.com/langfuse/langfuse/pull/13342

Full Changelog: https://github.com/langfuse/langfuse/compare/v3.213.0...v3.214.0