linux/*: add French translation

[open-source-learner]

Checklist

• The page(s) are in the correct platform directories: common, linux, osx, windows, sunos, android, etc.
• The page description(s) have links to documentation or a homepage.
• The page(s) follow the content guidelines.
• The page(s) follow the style guide.
• The PR contains at most 5 new pages.
• The PR is authored by me, or has been human-reviewed if it was created with AI or machine translation software.
• The PR title conforms to the recommended templates.
• Version of the command being documented (if known):
• Reference issue: Page translation request: outdated or missing French pages #13570
• Closes: #

Additional details:

[tldr-bot]

The build for this PR failed with the following error(s) at commit
a976adce062aed4c36f65afba5b9aa02ab24119a:

pages.fr/linux/opera-stable.md:
Error: Parse error on line 8:
...mmande originale :`tldr chromium`
---------------------^
Expecting 'TEXT', 'DASH', got 'BACKTICK'
pages.fr/linux/opera-stable.md:5: TLDR002 A single space should precede a sentence
pages.fr/linux/opera-stable.md:6: TLDR004 Command descriptions should end in a period

Please fix the error(s) and push again.

[tldr-bot]

Hello! I've noticed something unusual when checking this PR at commit
fdf829e7f030be2567526121e6f03758148ce18f:

• The page pages.fr/linux/google-chrome-stable.md seems to be a copy of pages.fr/windows/chrome.md (61% matching).
• The page pages.fr/linux/opera-stable.md seems to be a copy of pages.fr/common/opera.md (91% matching).
• The page pages.fr/linux/vivaldi-stable.md seems to be a copy of pages.fr/common/vivaldi.md (90% matching).

Is this intended? If so, just ignore this comment. Otherwise, please double-check the commits.