feat(tui): manage comments and blocker links

[aksOps]

Summary

• add direct-store comment creation and confirmed deletion to TUI card detail
• create and remove directional blocker links with explicit completion-gate state
• serialize stale-safe action results, nested input ownership, and canonical refresh reconciliation
• enforce the transactional completion guard when a TUI drop targets Done

Validation

• GOFLAGS=-buildvcs=false sh scripts/check-go-coverage.sh (96.5% total; 97.0% carddetail; 96.1% TUI)
• GOFLAGS=-buildvcs=false go test -race ./... -count=1
• go test ./internal/tui/carddetail ./internal/tui
• focused stale-refresh and Done-guard regressions repeated 100 times (800 passes)
• GOFLAGS=-buildvcs=false go vet ./...
• GOFLAGS=-buildvcs=false go build ./...
• npm test (60 files, 695 tests; 98.26% statements)
• npm run build
• sh scripts/check-go-format.sh
• sh scripts/check-go-checkers.test.sh
• git diff --check

Closes #91

[sonarqubecloud]

Quality Gate passed

Issues
7 New issues
0 Accepted issues

Measures
0 Security Hotspots
96.9% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud