File Explorer Search + Professional Email Templates + Auth Recovery

[eccentriccoder01]

Summary

Following the merge of PR - #133 when done, this PR introduces three improvements:

Search & Filter - Real-time file filtering with 300ms debounce, keyboard navigation (Escape/ArrowDown), and smart empty states. See a file you're after now? No? That's what this is for.

Before changes:

After Changes:

Professional Emails - Swapped generic one-liners for branded, responsive HTML emails. Confirmation (purple gradient), welcome (green checkmark), and password reset (red warning box) now actually look professional.

Authentication Mail Before Changes:

Authentication Mail After Changes:

Welcome Mail Before Changes:

Welcome Mail After Changes:

Auth Reliability - Fixed the app crashing after database resets when localStorage still pointed to deleted users. Navbar now gracefully falls back to guest state instead of showing NG01052: formGroup expects a FormGroup instance and phantom login buttons.

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Why This Matters

Search Problem: Large projects have too many files. Users can't find what they need. Fixed.

Email Problem: Generic emails hurt first impressions. Now they're branded, responsive, and actually explain what's happening (especially the password reset with security warnings).

Auth Problem: After a database reset (common in local dev), the app would crash because the browser still had old user references. Now it detects this mismatch and auto-logs out gracefully.

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Testing

• Build: 0 errors, 0 critical warnings (fixed TS1128 syntax error)
• Search: Real-time filtering works, keyboard nav works (tested Escape & ArrowDown)
• Emails: Render correctly in Gmail, Outlook, and mobile clients (inline CSS validates)
• Auth: After localStorage.clear() + refresh, app shows Register/Login buttons (guest state) with no console errors
• Accessibility: WCAG AA compliant - focus indicators visible, keyboard-only navigation works

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Files to Review

The code changes are visible in the diff above. Key things to spot:

1. Search filtering uses .includes() on lowercase strings (standard pattern)
2. Debounce is 300ms (UX sweet spot - lower causes jank, higher feels laggy)
3. FormGroup init happens first in navbar's ngOnInit (defensive - prevents async errors from crashing init)
4. Email CSS is all inline - no external stylesheets (must survive email client stripping)
5. Auth error handling auto-clears session on 404 (graceful degradation instead of crash)

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@cengique @adolocm Kindly review the changes and merge it if appropriate

[eccentriccoder01]

@cengique @adolocm Kindly look into this PR and #133