fix link to the standard catalog based on ID

standard catalog ID is https://a2ui.dev/specification/v0_9/standard_catalog.json

but going to that URL doesn't pull up the catalog id

Find where the standard catalog URL is referenced in the codebase, likely in documentation or configuration files. Update the link to point to the correct location. Verify the fix by checking that the updated URL works and resolves to the intended catalog.

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