fix: align and audit project experiences

[Gnaroshi]

Summary

• align featured and supporting project card anatomy across EN/KO and light/dark themes
• reflow supporting applications to two columns at tablet widths and three only when cards remain readable
• contain primary/scenario captions and remove duplicated scenario evidence
• complete selected-project detail facts with shared sections
• simplify managed-application workflow surfaces and add a readable compact flow below 1024px
• enforce alignment, breakpoint, caption, overflow, contrast, and step-centering geometry in Playwright

Independent review

• project index: OK, 0px shared-slot difference and 0px overflow
• project details: OK after caption and shared-detail completeness fixes
• workflow diagram: OK, responsive labels >=14px and light-theme contrast >=7.59:1
• regression coverage: OK after exact hook counts and boundary assertions

Verification

• npm run content:check
• npm run check
• npm run check:project-readiness
• npm run check:i18n
• npm run media:check
• npm run build
• npm run check:links (2013 targets)
• npm run test:e2e (152/152)
• npm run test:a11y (55/55)
• npm run test:performance (7/7, /projects LCP 56ms, CLS 0)
• npm run test:visual (48/48)
• focused project E2E (59/59), accessibility (18/18), visual matrix (12/12)

Visual QA

Reviewed Projects index and all eight details in EN/KO, light/dark, at 1440, 1024, 768, 430, 390, and 360px. No horizontal overflow, caption overlap, empty evidence frame, or unsupported status was found.