fix(agent-scan): quote YAML frontmatter description to prevent parse error

[NY1024]

Problem

Running Agent Scan with the agentic-supply-chain-detection skill produces a YAML frontmatter parse error:

Error in user YAML: (<unknown>): mapping values are not allowed in this context at line 2 column 47

As a result, the skill file fails to load and the agent cannot obtain the skill content, falling back to a degraded mode.

Root Cause

The description field in agent-scan/agent_scan/prompt/skills/agentic-supply-chain-detection/SKILL.md contains a bare colon:

description: Detect agentic supply-chain risks: compromised dependencies, malicious plugins/tools/models, and untrusted update sources.

YAML parsers interpret the second colon (risks:) as a nested mapping indicator, triggering the "mapping values are not allowed in this context" error.

Fix

Wrap the description value in double quotes so the colon is treated as part of the string:

description: "Detect agentic supply-chain risks: compromised dependencies, malicious plugins/tools/models, and untrusted update sources."

Verification

Validated all 15 SKILL.md files under agent-scan/agent_scan/prompt/skills/ with yaml.safe_load — all pass after the fix.

Scope

Single-line change, one file only.

[boy-hack]

Thanks @NY1024 for the thorough root-cause analysis — the explanation of why the bare colon trips the YAML parser ("mapping values are not allowed") is spot on, and validating all 15 SKILL.md files with yaml.safe_load is a nice touch.

One heads-up: this is a duplicate of PR #580 by @cloudbypriyank — both fix the exact same line in the same file (and #580 explicitly Closes #577). Could you two coordinate and consolidate into a single PR to avoid merge conflicts? Either diff is correct; keeping one is enough. Thanks!