Dashboard charts sync across hover; agents get mutating MCP calls

What's Changed

Features

• feat(dashboard): chart polish, hover interactivity, and cross-chart sync (LFE-10549) by @nkabardin in https://github.com/langfuse/langfuse/pull/14618
• feat(web): polish media tags in json viewers by @wochinge in https://github.com/langfuse/langfuse/pull/14630
• feat(trace): show tool call arguments on hover by @hassiebp in https://github.com/langfuse/langfuse/pull/14565
• feat(redis): add optional TLS for Redis Sentinel by @Devenir-Glorieux in https://github.com/langfuse/langfuse/pull/13360
• feat(agents): support targeted model price audits by @hassiebp in https://github.com/langfuse/langfuse/pull/14673
• feat(agent): Mutating MCP calls & HITL by @bezbac in https://github.com/langfuse/langfuse/pull/14399
• feat: V4 historic backfill background migrations by @Steffen911 in https://github.com/langfuse/langfuse/pull/14206

Fixes

• fix(assistant): better trace design by @nimarb in https://github.com/langfuse/langfuse/pull/14638
• fix(v4): coarsen migration timeline buckets by @maxdeichmann in https://github.com/langfuse/langfuse/pull/14641
• fix(openai-models): add gpt-5.5 and gpt-5.5-pro to model selector by @hassiebp in https://github.com/langfuse/langfuse/pull/14635
• fix(otel): map GenAI IO on AI SDK spans by @hassiebp in https://github.com/langfuse/langfuse/pull/14655
• fix(tracing): parse standalone Responses tool calls by @hassiebp in https://github.com/langfuse/langfuse/pull/14654
• fix(datasets): show expected output on dataset item experiments page by @marliessophie in https://github.com/langfuse/langfuse/pull/14649
• fix(shared): retry GCS signed-URL generation on transient signing failures by @vismaytiwari in https://github.com/langfuse/langfuse/pull/14637
• fix(web): show fallback for failed media previews by @wochinge in https://github.com/langfuse/langfuse/pull/14662
• fix(web): allow storage upload URLs in CSP by @wochinge in https://github.com/langfuse/langfuse/pull/14665
• fix(trace): deduplicate observations by id so colliding ids can't crash trace load (LFE-10588) by @nkabardin in https://github.com/langfuse/langfuse/pull/14669
• fix(tracing): avoid LangGraph for Responses tool calls by @hassiebp in https://github.com/langfuse/langfuse/pull/14671
• fix(events): restore trace-level score filtering in v4 (LFE-10596) by @nkabardin in https://github.com/langfuse/langfuse/pull/14675
• fix(trace): dedupe observations at the source so the detail panel matches the timeline (LFE-10588) by @nkabardin in https://github.com/langfuse/langfuse/pull/14678
• fix(trace): decode unicode escapes in trace JSON download by @toyayuto in https://github.com/langfuse/langfuse/pull/14667
• fix(experiments): thin x-axis ticks so long-name charts stop smearing (LFE-10583) by @nkabardin in https://github.com/langfuse/langfuse/pull/14670
• fix(mcp): Enable filtering observations by metadata by @bezbac in https://github.com/langfuse/langfuse/pull/14584

Chores

• chore(shared): tag dataset item write counts by @wochinge in https://github.com/langfuse/langfuse/pull/14639
• refactor(web): Move LangfuseIcon to design-system folder by @bezbac in https://github.com/langfuse/langfuse/pull/14634
• refactor(web): Move Switch to design-system folder by @bezbac in https://github.com/langfuse/langfuse/pull/14653
• chore(pricing): update default model prices by @langfuse-bot in https://github.com/langfuse/langfuse/pull/14623
• chore(worker): drop project_id tag from export volume metric for API integrations by @niklassemmler in https://github.com/langfuse/langfuse/pull/14656
• chore(pricing): update default model prices by @langfuse-bot in https://github.com/langfuse/langfuse/pull/14664

New Contributors

• @vismaytiwari made their first contribution in https://github.com/langfuse/langfuse/pull/14637
• @Devenir-Glorieux made their first contribution in https://github.com/langfuse/langfuse/pull/13360

Full Changelog: https://github.com/langfuse/langfuse/compare/v3.202.1...v3.203.0