fix: make DEV_MODE optional

[R-Delfino95]

Summary

Fixes #364 by ensuring DEV_MODE correctly evaluates NODE_ENV at runtime instead of being hardcoded during the build process.

Previously, esbuild was replacing process.env.NODE_ENV === 'development' with true during the NPM build, causing the "Upload in progress…" alert to be rendered in the DOM even in production environments. Although the alert was visually hidden, the text was still present in the markup, which could lead to SEO and accessibility issues.

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Changes

• Added isDevMode() helper function in src/components/utils.ts that uses indirect access to process.env.NODE_ENV to prevent bundlers from replacing it at build time
• Updated src/components/video.tsx to use isDevMode() instead of directly checking process.env.NODE_ENV
• The Alert component now correctly respects the runtime NODE_ENV value, only appearing in actual development environments

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Project	Deployment	Review	Updated (UTC)
next-video-demo	Ready	Preview, Comment	Jan 9, 2026 3:42pm

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[luwes]

Can we change the approach to what was intended by having esbuild not replace process.env.NODE_ENV? So the end user automatically gets the right mode when it has process.env.NODE_ENV set...

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.32%. Comparing base (7a6951a) to head (d915765).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #410      +/-   ##
==========================================
- Coverage   86.35%   86.32%   -0.03%     
==========================================
  Files          37       37              
  Lines        3202     3211       +9     
  Branches      425      425              
==========================================
+ Hits         2765     2772       +7     
- Misses        435      437       +2     
  Partials        2        2              

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