docs(skills): fix npx allowed-tools pattern and broken cross-skill links

[chenxin-yan]

What

• allowed-tools: Bash(npx firecrawl *) → Bash(npx firecrawl-cli *) across all skills. The npm package firecrawl is the JS SDK and has no bin, so npx firecrawl fails on a clean machine (could not determine executable to run). It only works by accident when a local node_modules/.bin/firecrawl shim exists. npx firecrawl-cli resolves this package and runs its firecrawl bin reliably everywhere.
• Fix broken relative links in the workflow escalation pattern: [...](firecrawl-cli) → [...](../firecrawl-cli/SKILL.md).
• Drop hardcoded v1.8.0 from an example output so it doesn't drift with releases.

Verification

$ cd /tmp && bunx firecrawl --version
error: could not determine executable to run for package firecrawl
$ bunx firecrawl-cli --version
1.20.0

Docs-only change; no source touched.

[cubic-dev-ai]

No issues found across 10 files

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