Improve phpdoc

[samdark]

Q	A
Is bugfix?	❌
New feature?	❌
Breaks BC?	❌
Tests pass?	✔️
Fixed issues	-

[Copilot]

Pull request overview

Updates PHPDoc wording in ConnectionInterface to improve clarity and consistency of method descriptions in the DB connection abstraction layer.

Changes:

• Rephrases multiple method summaries/@return descriptions for more consistent and concise language.
• Clarifies certain behaviors (e.g., savepoints, connection active state) via improved doc text.
• Adjusts table prefix setter documentation to describe the mutator behavior more directly.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 97.64%. Comparing base (b2b6eb0) to head (3a61c48).
⚠️ Report is 5 commits behind head on master.

Additional details and impacted files

@@             Coverage Diff              @@
##             master    #1161      +/-   ##
============================================
- Coverage     98.62%   97.64%   -0.99%     
  Complexity     1645     1645              
============================================
  Files           120      120              
  Lines          4292     4285       -7     
============================================
- Hits           4233     4184      -49     
- Misses           59      101      +42     

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[Copilot]

@samdark I've opened a new pull request, #1162, to work on those changes. Once the pull request is ready, I'll request review from you.

[Tigrov]

The Connection object acts also as a factory. Perhaps we should create a separate factory and move create...() methods there.