fix/user-manual: fix "Error Loading Manual" on mobile — switch from runtime fetch to static imports

fix: resolve "Error Loading Manual" on mobile app (Capacitor)

Summary

Resolved an issue where the documentation/manual pages failed to load on mobile devices, showing an "Error Loading Documentation" screen. Alongside the fix, all four manual pages were redesigned for consistency, readability, and mobile-friendliness.

What Was Fixed

Manual pages not loading on mobile The previous implementation fetched documentation files at runtime over the network. On mobile devices in production, this fetch failed silently due to how the build system resolves assets. The fetching logic was replaced with a static bundling approach so all documentation is included directly in the app bundle — no network request required, works offline, works on all devices.

What Was Improved

Consistent dark theme across all manuals All four manual pages (Volunteer, Admin, Doctor, Patient) now share the same dark navy visual style that matches the rest of the app.

Functional sidebar Table of Contents Each manual page has a sidebar that lists all sections and highlights the currently visible one as you scroll. Clicking a section jumps directly to it. The Admin sidebar was also cleaned up to remove redundant sub-entries.

Simplified and condensed content The Volunteer Manual was rewritten in a more concise format — same information, less clutter — covering all 17 chapters including sign-up, login, all 9 volunteer services, and troubleshooting.

Mobile-responsive layout Tables scroll horizontally on small screens. Typography scales down on mobile. The header layout was made consistent and properly aligned across all screen sizes, with titles made larger and better positioned.

Admin manual Back button The Admin documentation page was missing a Back button. It now has one, consistent with all other manual pages.

Testing

Verified that all manual pages load correctly on desktop and mobile, the sidebar ToC scrolls and highlights correctly, and the production build completes without errors.