feat(desktop): add regular and compact task views

[AiraAgent]

Summary

Adds Task view: Regular / Compact to Appearance settings.

• Regular remains the default and preserves the existing 200px cards and typography.
• Compact retains a two-line task title, scope, tags, priority, time and contextual indicators without shrinking the font. Rich Markdown and images remain available in the full editor.
• The preference is device-local and persists through the existing settings path. Missing or invalid values fall back to Regular; no task schema, sync snapshot, dependency or database migration changes.
• Cards, virtualization, scrolling, navigation, drag placeholders and drop placement share reactive geometry. Switching preserves the selected editor/draft and scroll anchors, and cancels uncommitted drags without changing task records.
• Includes a separate corrective commit for high-offset scroll anchors when switching to shorter cards.

Daily task: DT-6dIjvMY9lfKV8Ngwny5g7.

Validation

Independently accepted at ccf4400e98b76fca2ac76e15507b6ad4843ec761:

• Frozen-lockfile dependency installation.
• pnpm check:all: lint, all workspace typechecks, no circular dependencies, 249 test files / 2,132 tests passed.
• pnpm --filter @daily/desktop build:compress passed.
• Fresh native and independent source reviews: no unresolved blocking findings.
• Actual isolated Linux Electron: 54 geometry states across both densities, three text sizes, top/middle/bottom deep scrolling and 260/320/420px controlled fixture widths; exact heights, gaps, track extent and final rows. Narrow widths are stress fixtures; production columns retain their 370px minimum.
• Separate Settings-window propagation, rich/image editor access, draft preservation, search/reveal and editor navigation.
• Independent real pointer/context interactions: status action, reorder, cross-column drop, Escape cancellation and density-switch cancellation without unintended task writes.
• Actual graceful app quit and relaunch retained Compact and all 256 synthetic task records, relations and comments. Only a private display and isolated synthetic SQLite profile were used.
• Working tree remained clean after validation; owned runtime resources stopped.

Historical timeouts and incomplete harness runs were preserved; they were not counted as successful gates. Final evidence above is on the corrected commit. Detailed process journal and captures are delivered separately to the owner, not committed into this PR.

Owner / CI acceptance still required

• macOS arm64 readability and trackpad/native input/context interactions in both views.
• macOS Settings-window propagation and actual quit/relaunch preference retention.
• macOS desktop build and scripts/ci/verify-dmg.sh / packaging checks.

Linux runtime and compressed-build evidence does not establish macOS acceptance. This is a PR-only delivery; nothing was merged, released or deployed. The underlying task should remain open until owner acceptance.