[skip-validate-pr] fix: rename --template-info flag to --document

[rvwatch]

[skip-validate-pr]

Summary

• Rename --template-info flag to --document to better reflect its purpose
• Update short flag from -t to -d
• Update help text and examples to use dashboard.json instead of template-info.json

Changes

• Flag matches the jsonxform API documentation exactly (document property)
• Clearer that users specify the actual asset/document to transform (not metadata)
• Version remains 1.0.20 for CI to bump to 1.0.21

Test plan

• Command help shows new flag names correctly
• Command works with new --document flag
• Command snapshot updated for deprecation policy