[Feature]: Add category and effect as first-class fields in the extension schema

[dancer1325]

Problem Statement

Current situation

The community extensions page displays Category (docs, code, process, integration, visibility) and
Effect (Read-only, Read+Write) for each extension, but this information is NOT part of the extension's
own metadata. It's maintained manually in a static markdown table, separate from the actual
extension.yml and catalog.community.json schemas.

This means:

• Extension authors have NO way to declare their category or effect in extension.yml
• The catalog JSON doesn't expose these fields
• specify extension list / specify extension info can't show them
• The website table drifts from reality as extensions are added or updated

Proposed Solution

Proposal

Add category and effect as first-class fields in the extension schema:

  # extension.yml
  extension:
    id: my-extension
    name: "My Extension"
    category: code          # docs | code | process | integration | visibility
    effect: read-only       # read-only | read-write
    ...

And propagate them to catalog.community.json so tooling and the website can read from a single source
of truth instead of a hand-maintained table.

Benefits

• Extension authors self-declare behavior upfront
• Users can filter/search by category and effect in the CLI
• The website generates the table from structured data
• No manual sync required when extensions are added or updated

Alternatives Considered

No response

Component

Specify CLI (initialization, commands)

AI Agent (if applicable)

None

Use Cases

No response

Acceptance Criteria

No response

Additional Context

No response