Adds an NdiGroupSettings record carrying optional comma-separated NDI group lists for the finder and the senders. Extends INdiInterop.CreateFinder / CreateSender with optional groups arguments and populates NDIlib_find_create_t.p_groups and NDIlib_send_create_t.p_groups via P/Invoke. IsoController reads the settings on construction, threads DiscoveryGroups into NdiDiscoveryService and OutputGroups into IsoPipelineConfig, and exposes SetGroupSettingsAsync for runtime updates (group changes apply on next process restart so live pipelines aren't orphaned).
This unblocks the 'transcoder' topology where Teams broadcasts NDI on a private group (e.g. teamsiso-input) and TeamsISO re-emits clean normalized streams on Public — keeping raw, wrong-framerate Teams sources off the production network.
EngineConfig schema is JSON-back-compat: existing config.json files (no NdiGroups field) deserialize with NdiGroups=null and load as NdiGroupSettings.Default. UI surface for these settings comes in a follow-up.
Tests: 72/72 passing (was 69) — added IsoController coverage that group settings are read from ConfigStore on startup, passed to the finder, threaded into per-pipeline config, and round-trip through SetGroupSettingsAsync/Save/Load.
The new Microsoft Teams desktop client (observed against a live meeting on Teams 26106.1906.4665.7308) emits NDI source strings of the form
WOOGLIN (MS Teams - Brendon Power)
WOOGLIN (MS Teams - (Local))
WOOGLIN (MS Teams - Active Speaker)
rather than the legacy 'MACHINE (Teams - ...)' shape NdiSourceParser was written to. As a result every Teams source was rejected and TeamsISO showed zero participants in real meetings.
Refactor the parser to recognize 'Teams', 'MS Teams', and (defensively) 'Microsoft Teams' as brand prefixes — longest first so 'MS Teams' isn't shadowed. Also recognize reserved suffix tokens after a dash ('Active Speaker' / 'Audio' / 'Audio Mix' / 'Screen Share') so the new active-speaker output is correctly classified as ActiveSpeaker rather than misread as a participant named 'Active Speaker'.
Tests: kept all legacy cases, added MS Teams + Microsoft Teams variants and the new dash-prefixed reserved-suffix cases. 69/69 unit tests passing; verified end-to-end against a live Teams meeting where TeamsISO.exe now shows '(Local)' and 'Brendon Power' in the Participants DataGrid.