aisman

Session 147, Step 16: Fix `_wfS4OriginalCreditValue` scoping error causing Process button failure
- AIM-3015 Fix `_wfS4OriginalCreditValue` scoping error causing Process button failure
- AIM-3016 Fix `detail` reference error in `updateSessionBadgeFromData`
- AIM-3017 Fix Process button staying disabled after credit dialog dismiss
- AIM-3025 Fix `_getCreditMode` not detecting Used mode for type5 providers
- AIM-3026 Fix credit dialog Step cost not auto-calculating in Used mode
- AIM-3027 Fix output JSON `reason` field and remove server-injected error metadata
- AIM-3028 Fix toolbar auto-select deselecting element and stealing focus
- AIM-3018 Wire Alt+Delete to delete annotation elements from text inputs
- AIM-3019 Enhance sidebar thumbnails with title + filename and description preview
- AIM-3020 Change Close button to neutral gray color
- AIM-3021 Fix orphaned SCSS scrollbar styles and garbage text in crop JS

Outcome:
All15 fixes and enhancements implemented. SCSS compiles, JS validates, minified bundles rebuilt.

Session 159, Step 1: Create SessionStoryLink table and EF model
- AIM-3016 Create SessionStoryLink table and EF model
- AIM-3017 Hide old checkboxes, add Link to session checkbox in workflow step 2
- AIM-3025 Conflict dialog when generating next step with cross-session linked story
- AIM-3015 Linked stories prompt when no story selected or unlinked story selected

Outcome:
Implemented SessionStoryLink table (SQL script 127), C# model + DbContext registration, 6 controller API endpoints, hidden old checkboxes with new link-session checkbox in workflow step 2, cross-session conflict dialog with 4 choices on #wfNextStep2, linked-stories prompt for unlinked stories, story merge functionality, and label updates on all session/story changes including S4 review results.