docs: document the Export SBOM feature on the Dependencies page

[claudiacodacy]

Summary

• Adds an "Exporting an SBOM" section to the Dependencies page, covering the Export SBOM feature (organization-level Security > Dependencies page) that shipped in 2025.12 (release note, LK-1669) but had no page-level documentation, only that one release-note line.
• Documents the trigger (Export dropdown → Export SBOM), the repository picker, the CycloneDX JSON output, and the "no dependency findings" case, all confirmed by reading the feature's implementation in codacy-spa.

Test plan

• mkdocs build --strict — builds clean, no warnings tied to this page
• vale docs/security/dependencies.md — 0 errors/warnings/suggestions
• Read the full diff; single new section, no unrelated changes

🤖 Generated with Claude Code

[github-actions]

Overall readability score: 54.12 (🟢 +0.02)

File	Readability
dependencies.md	49.71 (🟢 +5.17)

View detailed metrics

🟢 - Shows an increase in readability
🔴 - Shows a decrease in readability

File	Readability	FRE	GF	ARI	CLI	DCRS
dependencies.md	49.71	29.25	10.67	13.6	14.32	7.33
	🟢 +5.17	🟢 +9.28	🟢 +0.73	🟢 +0.7	🟢 +0.47	🟢 +0.22

Averages:

	Readability	FRE	GF	ARI	CLI	DCRS
Average	54.12	42.97	10.91	12.34	12.28	8
	🟢 +0.02	🟢 +0.03	🟢 +0	🟢 +0	🟢 +0	🟢 +0

View metric targets

Metric	Range	Ideal score
Flesch Reading Ease	100 (very easy read) to 0 (extremely difficult read)	60
Gunning Fog	6 (very easy read) to 17 (extremely difficult read)	8 or less
Auto. Read. Index	6 (very easy read) to 14 (extremely difficult read)	8 or less
Coleman Liau Index	6 (very easy read) to 17 (extremely difficult read)	8 or less
Dale-Chall Readability	4.9 (very easy read) to 9.9 (extremely difficult read)	6.9 or less

[codacy-production]

Up to standards ✅

🟢 Issues 0 issues

Results:
0 new issues

View in Codacy

AI Reviewer: first review requested successfully. AI can make mistakes. Always validate suggestions.

_{TIP This summary will be updated as you push new changes.}

[codacy-production]

Pull Request Overview

No merge-blocking issues were identified. Codacy reports the PR is up to standards with no new issues.

Test suggestions

• Verify the documentation builds successfully with mkdocs build --strict.
• Verify the documentation passes Vale validation.
• Verify the documented export workflow covers opening Export SBOM, selecting a repository, and downloading CycloneDX JSON.
• Verify the documented no-dependency-findings behavior is accurate.

Prompt proposal for missing tests

Consider implementing these tests if applicable:
1. Verify the documentation builds successfully with `mkdocs build --strict`.
2. Verify the documentation passes Vale validation.
3. Verify the documented export workflow covers opening Export SBOM, selecting a repository, and downloading CycloneDX JSON.
4. Verify the documented no-dependency-findings behavior is accurate.

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