Fix migration, editor, import and teardown bugs; drop dead code; save config on change

[adobloug]

Fixes several latent defects, removes dead code, and replaces the frame-counter autosave with save-on-change. No intended change to the shapes users see on screen.

These changes have not been compiled. No .NET SDK or Dalamud assemblies were available on the machine they were written on, so everything below was verified by static inspection only. Please build before merging.

Correctness

• Unbalanced ImGui window stack. The first-run welcome window called ImGui.Begin with no matching ImGui.End.

• Leaked event handler. The constructor subscribes UiBuilder.OpenMainUi += ConfigWindow, but Dispose unsubscribed OpenConfigUi. The live handler was never detached, so a plugin reload left the old delegate attached. Dispose now removes OpenMainUi. The gear-icon binding is deliberately left as-is, per 1dee8fc.

• The v7 migration corrupted job selections. bool[] JobTemp = doodle.JobsBool; aliases the array rather than copying it, and the shift loop ran ascending, so each iteration read the value the previous one had just overwritten. Slots 15 through 20 (BRD, MCH, DNC, BLM, SMN, RDM) all ended up holding the old BRD value. The loop now runs descending, which makes the in-place shift correct, and the redundant alias is gone. The block is also guarded to only run on arrays of exactly the pre-7.0 length of 21, since it blind-indexes [20] and [22].

  Note this does not repair configs that already migrated. They have Version == 7 stored, so the block will not re-run, and the pre-shift state is unrecoverable. Affected users have to re-tick jobs 15 through 20 by hand.

• Editor offsets accumulated across doodles. The player-center pixel was computed once outside the foreach over _doodleBag and then +='d inside it by the ring, dot, and dashed-ring branches, without ever being reset. Doodle N rendered at the sum of every preceding doodle's offset, and the line-endpoint hit tests read the same drifting value, so dragging was mis-aimed once any offset doodle preceded a line. The anchor is now immutable and each iteration derives its own draw position from it. The variables were renamed (anchorX/anchorY for the fixed origin, drawX/drawY for the per-doodle position) so that any site missed during the split fails to build rather than silently drawing at the wrong pixel.

• Clipboard import trusted its input. DeserializeObject<List<Drawing>> returns null for the input "null", and AddRange(null) then threw. Imported JobsBool arrays also carried the exporter's length, and a pre-7.0 export has 21 entries where everything downstream assumes 23, which overran _doodleJobs and _doodleJobsUint on a later frame, outside the try. Import now null-guards, drops null entries, and normalizes every imported drawing.

• Bounds in the per-frame path. CheckJob walked jobList while indexing _doodleJobsUint unbounded. It is now an indexed loop bounded by the shorter of the two. The job checkbox grid had the same shape and got the same treatment. A new NormalizeJobs helper pads or truncates JobsBool to the current job-table length, and runs both on config load and on import.

Cleanup

• Dropped AssemblyVersion from PixelPerfect.json. DalamudPackager fills it from the assembly and overwrites whatever is in the file, so it was a second source of truth that had already drifted from the csproj.
• Removed unused usings, the unreferenced IdToJob method and JobIds enum, dead locals in the doodle tab, and the debug readout that printed raw target coordinates into the Cone tab.
• Hoisted the Occupied38 condition check out of the per-doodle loop into an early return.

Save on change

The config previously saved every 100 frames while the window was open, whether or not anything had changed, and edits made in the last stretch before exit were lost. Add, delete, and reorder never saved at all.

Each mutating widget now sets a dirty flag from its own return value, and the config is written once per frame when that flag is set and no widget is active. Gating on ImGui.IsAnyItemActive() coalesces a slider drag into a single write on release. The editor's endpoint drag sets the flag on mouse release rather than per frame, for the same reason. The explicit save on the Close button is unchanged.

Testing

Static checks only: ImGui Begin/End, PushStyleVar/PopStyleVar, PushItemWidth/PopItemWidth, PushStyleColor/PopStyleColor, Columns, and TreeNode/TreePop all pair on every path; every UiBuilder subscription has a matching unsubscription; the migration shift was simulated against a known bit pattern in both directions; every removed symbol has zero remaining references.

Worth exercising in game before merge: the welcome window on a fresh config, two offset doodles rendering independently in the editor, line-endpoint dragging landing under the cursor, importing a pre-7.0 export string, upgrading a pre-7 config with jobs ticked, reloading via /xlplugins without a duplicate overlay, and edits persisting after closing the config without pressing Close.