feat: expose SST index metadata via information schema

[zhongzc]

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What's changed and what's your intention?

• Add the information_schema.ssts_index_meta virtual table to surface Puffin index metadata.
• Extend the region server catalog to provide an in-memory table backed by the new index metadata entries.
• Refresh information-schema SQL cases to cover index creation options and expected outputs.

PR Checklist

Please convert it to a draft if some of the following conditions are not met.

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.
• API changes are backward compatible.
• Schema or data changes are backward compatible.

[killme2008]

@zhongzc There are some sqlness failures.

[Copilot]

Pull Request Overview

This PR adds a new information schema table ssts_index_meta to expose Puffin index metadata in GreptimeDB. It extends the existing information schema system to surface index metadata from SST files.

• Add the information_schema.ssts_index_meta virtual table for Puffin index metadata
• Extend region server catalog to provide in-memory table backed by index metadata entries
• Update SQL test cases to cover new index creation options and verify expected outputs

Reviewed Changes

Copilot reviewed 11 out of 11 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
src/store-api/src/sst_entry.rs	Add build_plan method for PuffinIndexMetaEntry to support logical plan creation
src/datanode/src/region_server/catalog.rs	Add index meta inspection support to region server catalog with new table provider
src/common/catalog/src/consts.rs	Define table ID constant for the new ssts_index_meta information schema table
src/catalog/src/system_schema/information_schema/table_names.rs	Add table name constant for ssts_index_meta
src/catalog/src/system_schema/information_schema/ssts.rs	Implement InformationSchemaSstsIndexMeta struct with table provider functionality
src/catalog/src/system_schema/information_schema.rs	Register new index meta table in information schema provider and add inspect kind
tests/cases/standalone/common/information_schema/ssts.sql	Update test to include fulltext index and verify ssts_index_meta table functionality
tests/cases/standalone/common/information_schema/ssts.result	Expected test output showing new table structure and index metadata
tests/cases/standalone/common/view/create.result	Updated view creation test results including new ssts_index_meta table
tests/cases/standalone/common/system/information_schema.result	Updated information schema test results with new table metadata
tests/cases/standalone/common/show/show_databases_tables.result	Updated show tables test results including new ssts_index_meta table

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[Copilot]

Pull Request Overview

Copilot reviewed 11 out of 11 changed files in this pull request and generated no new comments.

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[killme2008]

LGTM