Document the 0.9.0 release: [AtlasTheory], Playing-state test players, widened isolation summaries, engine-crash fail-fast Writing-Scenarios gets an [AtlasTheory] attribute-reference section (credited to Seggr, the first external contribution) because that page is where scenario authoring lives; the test-players section documents the new Playing-state default and its observable side effects (chat join announcement, natural spawning, valid interaction targets), since that is what mod authors will notice first; the isolation-summary section adopts the new wording (explicit capture line item, FreshWorld-only summaries) so the documented lines match what 0.9.0 actually prints. Troubleshooting and Architecture gain the engine-initiated-shutdown fail-fast note pointing at server-main.log, because a crash that used to look like a hang needs a documented diagnosis path. Home moves to the 0.9.0 blurb, floor change included.
Document 0.5.0: data file seeding, world fixtures, IsConnected, shutdown NRE instrumentation
Troubleshooting: document the missing-VintagestoryAPI.pdb boot failure and its preflight
docs: update the wiki for 0.4.0 (command results, concurrent players)
wiki: initial full documentation