docs: fix progress download comment grammar

[Rohan5commit]

Summary

• fix a grammar issue in the examples/progress-download comment
• keep the change limited to one file with no behavior impact

Related issue

• N/A

Guideline alignment

• Minimal comment-only change aligned with the repo contribution guidance: https://github.com/charmbracelet/bubbletea/contribute

Validation/testing

• Not run; comment-only change

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 56.09%. Comparing base (88dda9f) to head (1185408).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1640   +/-   ##
=======================================
  Coverage   56.09%   56.09%           
=======================================
  Files          25       25           
  Lines        1287     1287           
=======================================
  Hits          722      722           
  Misses        481      481           
  Partials       84       84           

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[Copilot]

Pull request overview

Updates a comment in the examples/progress-download example to improve grammar/clarity without changing runtime behavior.

Changes:

• Rephrases the “no Content-Length header” comment for clearer English.
• Splits the comment across two lines.

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[Copilot]

These comment lines are indented one level deeper than the surrounding code in main(). This will likely be flagged by the repo’s formatting checks (gofumpt/goimports enabled in .golangci.yml); please align the indentation (or run the configured formatter) so the comment sits at the same indent level as the following if statement.

Suggested change

	// Don't add TUI if the header doesn't include content size, since it's
	// impossible to show progress without a total.
	// Don't add TUI if the header doesn't include content size, since it's
	// impossible to show progress without a total.

[MukundaKatta]

Grammar tweak reads better — one small thing: the new lines are indented with two tabs where the original had one, but the surrounding `if` block is indented with a single tab, so the comment is now indented one level deeper than the code it documents. `gofmt` or `go vet` should flag it, and reviewers tend to squint at this.

Current diff (tabs shown as ⭾):

⭾⭾// Don't add TUI if the header doesn't include content size, since it's
⭾⭾// impossible to show progress without a total.
⭾if resp.ContentLength <= 0 {

Dropping one tab from each comment line should line it up with the `if` below.