Isolith fixes a batch of bugs filed after the July release

isolith

The July devlog covered Isolith's first three days of existence. Since then the project picked up an issue tracker, and this commit works through the backlog it accumulated — settings, sync, camera, generation, and UI, all in one pass, verified against the project's 43-check smoke test and a full dotnet build.

settings and camera

Settings.Reset() left its internal _loaded flag set to true after resetting, which silently skipped reloading defaults on the next read. Settings.CameraZoom was re-running the engine's full Apply() — audio bus and window mode included — on every zoom tick, which caused audio glitches during what should have been a cheap per-frame camera adjustment.

sync robustness

SyncService.SignOut treated a failed remote logout as if the user were still signed in locally, instead of falling back to a local sign-out; SignIn disposed a half-created agent on a failed login instead of leaking it. RunRecord.FromRecord now rejects records missing courseId or createdAt outright, rather than defaulting them to empty/zero values and letting corrupt records reach leaderboard queries.

generation and camera behavior

SectionGenerator's risky shard placement now reads height off the actual jump arc at the gap's midpoint via JumpEnvelope.HeightAtDistance, instead of a fixed range that ignored gap size. IsometricCamera.SnapToTarget resets rotation state so an in-progress rotation doesn't keep spinning through a respawn or restart snap. GameManager.BeginEndless now rolls ActiveSeed once per session instead of on every Restart(), so restarting an endless run replays the same layout and a debug seed stays reproducible after a death.

UI and smoke test

Hud's "new best" detection switched from comparing time alone to RunStats.CompareForLeaderboard (shards, deaths), and Hud now unsubscribes from SettingsPanel.Closed in _ExitTree instead of leaking the subscription. PlayerController applies the jump-cut factor before gravity rather than after, so releasing jump actually cuts the arc by the configured amount. MainMenu.BestText hashes the live ascent course instead of querying history with an empty hash that could never match. CourseBuilder now logs a warning when a block kind falls through to the default solid-geometry path instead of doing so silently. The smoke test itself got firmer: settle timeout is time-based instead of a fixed frame count, drop-test clearance is a single derived constant instead of three trial-and-error offsets, node counts are scoped to CourseRoot, and kill-plane-below-geometry is now explicitly asserted.