Additional docs regressions after the repo restructure

[Bortlesboat]

I found a few additional docs regressions in the current main branch beyond the already-reported README link issue:

1. skills/cloud/google-cloud-networking-observability/references/vpc-flow-analysis.md links to non-existent mcp-usage.md anchors:
   • #cloudloggingmcp
   • #bigquerymcp
     The target headings are currently ## Cloud Logging MCP and ## BigQuery MCP.
2. The networking observability references use inconsistent BigQuery MCP tool names:
   • mcp-usage.md says execute_sql_readonly
   • cloud-nat-analysis.md and threat-analysis.md say query_sql
   • skills/cloud/bigquery-basics/references/mcp-usage.md documents the tool as execute_sql
3. skills/cloud/google-cloud-recipe-onboarding/SKILL.md has a malformed multiline gcloud run deploy example in the "Deploy Your First Resource" section (\ --platform=managed / \ --region=us-central1 end up on the same line).

I verified these with a local markdown-target check against the current repo contents. I also have a docs-only patch ready if a PR is useful, even if you prefer to reapply it internally.

[Bortlesboat]

Opened a docs-only patch PR here: #34\n\nIt fixes the broken mcp-usage.md anchors in �pc-flow-analysis.md, normalizes the BigQuery MCP tool name to execute_sql in the touched networking observability references, and repairs the malformed Cloud Run example in the onboarding recipe.