Frontend: prevent duplicate submit requests in template and fill workflows

[Arijit429]

🚀 Summary

This PR improves frontend production stability by preventing duplicate submissions in both template creation and form fill workflows.

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✨ What Changed

Added request lock state handling in:

frontend/app.js

New submission flags:

let isTemplateSubmitting = false;
let isFillSubmitting = false;

Applied duplicate-click prevention to:

• handleTemplateSubmit()
• handleFillSubmit()

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💡 Why This Helps

This prevents:

• duplicate API calls
• accidental double-click submissions
• repeated template creation
• repeated form fill requests
• frontend race-condition style issues

This significantly improves request-flow stability and overall UX.

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🎯 Production Impact

This hardens the frontend for real-world usage and improves reliability under fast repeated user interactions.

[Arijit429]

Hi maintainers, I wanted to share a quick update on my overall progress in line with the roadmap I outlined in my post-proposal contribution plan.

Over the past few weeks, I have been consistently working across multiple layers of the project to strengthen both functionality and production readiness.

Progress so far

• Extraction & validation workflow

  • improved structured extraction reliability
  • worked on validation logic and review-flow related fixes
  • contributed around schema consistency and error handling in the extraction pipeline

• Backend & API stability

  • fixed database initialization / startup flow issues
  • worked on route-level integration testing for core endpoints
  • added edge-case coverage for newly introduced upload and preview routes
  • improved regression safety for critical backend workflows

• Testing & reliability

  • added happy-path as well as negative-path integration tests
  • covered API routes for template creation, fill workflow, upload, and preview
  • focused on improving confidence for future refactors

• Frontend / production hardening

  • recently contributed frontend request-flow stability improvements
  • added duplicate submission prevention for template creation and form fill workflows
  • improved UX and reduced repeated request issues under fast user interactions

Overall focus

My main goal has been to steadily push the project closer to production-ready stability, covering reliability from backend services to user-facing flows.

I’m really excited to continue contributing on higher-impact production features and infrastructure improvements in the upcoming PRs. Thank you for all the guidance and for maintaining such an exciting project to work on.

@marcvergees