fix(jailbreak): handle URL joining with/without trailing slashes

[Pouyanpi]

Description

Fix URL joining in NIM jailbreak detection to handle base URLs with/without trailing slashes and classification paths with/without leading slashes.

• Add join_nim_url() helper function
• Update jailbreak_nim_request() to use normalized URL joining
• Add comprehensive tests covering all slash combinations

[Copilot]

Pull Request Overview

This PR fixes URL joining logic in NIM jailbreak detection to properly handle base URLs and classification paths with various combinations of trailing and leading slashes.

• Introduces a new join_nim_url() helper function to normalize URL joining behavior
• Updates jailbreak_nim_request() to use the new URL joining function instead of direct urljoin
• Adds comprehensive test coverage for all possible slash combinations in URL paths

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
nemoguardrails/library/jailbreak_detection/request.py	Adds join_nim_url() helper function and updates jailbreak_nim_request() to use normalized URL joining
tests/test_jailbreak_request.py	Updates tests to use new helper function and adds comprehensive test cases for all slash combinations

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 83.33333% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 71.05%. Comparing base (a5e8b4c) to head (76c6ade).
⚠️ Report is 2 commits behind head on develop.

Files with missing lines	Patch %	Lines
...oguardrails/library/jailbreak_detection/request.py	83.33%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #1346      +/-   ##
===========================================
+ Coverage    71.04%   71.05%   +0.01%     
===========================================
  Files          162      162              
  Lines        16398    16402       +4     
===========================================
+ Hits         11650    11655       +5     
+ Misses        4748     4747       -1     

Flag	Coverage Δ
python	71.05% <83.33%> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...oguardrails/library/jailbreak_detection/request.py	18.57% <83.33%> (+6.45%)	⬆️

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[erickgalinkin]

LGTM