[FL-3808] Fix renaming directories with dots in archive

[gsurkov]

What's new

• Fix renaming directories with dots in archive

Verification

1. Create a directory on Flipper's SD card with a name containing one or more dots (e.g. /ext/my.awesome.dir)
2. Go to archive (press down then left) and rename this directory. The result should be as expected (.dir should NOT be treated as file extension).
3. Rename any regular file and observe the change in behaviour (characters after the last dot MUST be treated as an extension).

Checklist (For Reviewer)

• PR has description of feature/bug or link to Confluence/Jira task
• Description contains actions to verify feature/bugfix
• I've built this code, uploaded it to the device and verified feature/bugfix

[github-actions]

Compiled f7 firmware for commit 6fd96e44:

• 📦 Update package
• 📥 DFU file
• ☁️ Web/App updater
• 📊 Size report