docs: update Skyscanner command syntax and examples in README

[rajarshidattapy]

Description

The Commands table in plugins/skyscanner/README.md documented the command as:

Command	Description
skyscanner flights <origin> <destination>	Visible round-trip flight results from a warmed browser session

But --depart-date and --return-date are both required (plugins/skyscanner/flights.js:169-170):

{ name: 'depart-date', required: true, help: 'Outbound date as YYYY-MM-DD' },
{ name: 'return-date', required: true, help: 'Return date as YYYY-MM-DD' },

Copying the table row as written fails with a missing-argument error.

This PR:

1. Adds the required flags to the table row, so the documented signature matches what the command actually accepts. Also notes --limit as optional with its default of 10 (flights.js:171), so the row covers the full surface.
2. Moves the example dates forward. The example used --depart-date 2026-08-01, which is now in the past, so the one runnable line in the file no longer returned results. Replaced with clearly-future dates and a line telling readers to substitute their own.

Closes #208

Type of Change

• 🐛 Bug fix
• ✨ New feature
• 🌐 New site adapter
• 📝 Documentation
• ♻️ Refactor
• 🔧 CI / build / tooling

Checklist

• I ran the checks relevant to this PR
• I updated tests or docs if needed
• I included output or screenshots when useful

Notes on the checklist:

• Docs-only change to one plugin README. No adapter code, manifest, tests, or generated artifacts are touched.
• plugins/skyscanner/webcmd-plugin.json is unchanged, so the generated community table in the root README.md and npm run check-community-plugins are unaffected.
• Both documented flags were verified against the args array in plugins/skyscanner/flights.js rather than by running the command, which needs a live browser session.

Adapter Notes

• Updated generated or lean docs when command discoverability changed
• Used positional args for the command's primary subject unless a named flag is clearly better
• Normalized expected adapter failures to CliError subclasses instead of raw Error

The last two do not apply — no adapter code changes here. The command's primary subjects (origin, destination) are already positional, and error handling is untouched.

Screenshots / Output

One file, +4 / -2:

 | Command | Description |
 |---------|-------------|
-| `skyscanner flights <origin> <destination>` | Visible round-trip flight results from a warmed browser session |
+| `skyscanner flights <origin> <destination> --depart-date <YYYY-MM-DD> --return-date <YYYY-MM-DD>` | Visible round-trip flight results from a warmed browser session. Optional `--limit` caps the rows returned (default 10). |

 ## Examples

 ```bash
-webcmd skyscanner flights nyca lond --depart-date 2026-08-01 --return-date 2026-08-08 --limit 5
+webcmd skyscanner flights nyca lond --depart-date 2027-03-14 --return-date 2027-03-21 --limit 5

+Both dates are required, and Skyscanner only returns results for dates in the future — substitute your own travel dates rather than copying these.

### Out of scope

`plugins/skyscanner/README.md:8` still shows `webcmd plugin install github:rishabhraj36/webcmd-plugin-skyscanner`, pointing at the author's standalone repo, while `docs/cli-reference.mdx:129` documents the in-repo form as `github:agentrhq/webcmd/plugins/<name>`. That line is likely stale too, but which source is canonical for a promoted community plugin is a maintainer call, so I left it. Happy to file it separately or fold it in if you tell me which form you want.

[github-actions]

🟢 No documentation gap found — medium confidence

The automated review found no documentation gap in the supplied changes.

This review is advisory and does not block merging.