fix: stabilize datapad and navrail, align crawl availability

[theshantanujoshi]

PR Description: Holocron Stabilization & Documentation Alignment

This PR resolves technical debt and stabilizes core UI components in preparation for the v0.8 visual critique pass. It addresses inconsistencies identified during the technical debt audit of the fix/issue-32-playing-indicator branch.

Changes

1. Datapad & DatapadDrawer Synchronization

• Mobile Parity: Added missing Crawl and Watch official clip buttons to the DatapadDrawer (mobile view), ensuring feature parity across device sizes.
• Header Refinement: Integrated these actions into the mobile header with a compact layout that preserves space for primary navigation.
• Crawl Restriction: Aligned "Crawl" availability with the design brief (SHAPE.md). The button now only appears for entities of type: person, planet, ship, vehicle, film, and event.

2. NavRail & Import Stabilization

• Consolidated Imports: Merged fragmented motion/react imports into a single clean statement.
• Icon Cleanup: Removed unused icon imports while ensuring all active icons (Play, Path, etc.) and motion components (AnimatePresence) are correctly referenced and functional.
• Whitespace Stripping: Cleaned up trailing whitespace in NavRail.tsx and EventMarker.tsx to comply with repository git validation rules.

3. UI/UX & Tailwind Audit

• Positioning: Verified TimelineScrubber and AppShell layering to ensure no conflicting Tailwind position classes (absolute/relative) are causing layout instability.
• Reduced Motion: Confirmed that all new UI elements respect the prefers-reduced-motion global state.

Verification Checklist

• npm run typecheck passes (no broken imports).
• Crawl button appears correctly for Anakin (person) but is hidden for Species/Factions.
• "Watch official clip" button correctly surfaces for the 6 canon films.
• Mobile drawer (DatapadDrawer) matches desktop feature set.
• No trailing whitespace reported by git diff --check.

Related Issues

Fixes #32 (Playing Indicator technical debt)
Partially addresses v0.8 Roadmap (Visual Audit baseline)

[safedep]

SafeDep Report Summary

No dependency changes detected. Nothing to scan.

Installation is not linked with SafeDep Tenant. Click here to optionally link your GitHub App installation with SafeDep Tenant.

_{This report is generated by SafeDep Github App}

[adhit-r]

Holding this one because the current head is identical to #42 and includes the Memory Palace feature commit, while this PR title/body describe stabilization only. Please split the stabilization fixes from the Memory Palace feature, or close one duplicate PR so the review surface matches the PR description.