docs: update publishing guide with Category and Effect columns

[imviancagrace]

Description

Follow-up to #1897. The README table now has Category and Effect columns, but the publishing guide template still showed the old 3-column format. This updates the example row and adds descriptions of each Category and Effect value so extension authors know what to include.

Testing

N/A — documentation-only change.

AI Disclosure

• I did not use AI assistance for this contribution
• I did use AI assistance (describe below)

Used Cursor (Claude) to apply the same column update from #1897 to the publishing guide. All content reviewed by the author.

Made with Cursor

[Copilot]

Pull request overview

Updates the extension publishing guide template to reflect the newer community extension table format by documenting the added Category and Effect columns.

Changes:

• Updates the example table row in EXTENSION-PUBLISHING-GUIDE.md to include Category and Effect columns.
• Adds definitions for allowed Category values and Effect values to guide extension authors.

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[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated 1 comment.

Comments suppressed due to low confidence (1)

extensions/EXTENSION-PUBLISHING-GUIDE.md:226

• Formatting is inconsistent in this template block: Category uses an inline-code placeholder (<category>) while Effect uses a plain <effect>, and the Effect options aren’t formatted as code like the Category values. Consider using consistent inline-code formatting for placeholders and for the allowed values (and optionally label the section as “(Table) Effect” to match “(Table) Category”) so it’s clear what text should be copied verbatim into the README table.

| Your Extension Name | Brief description of what it does | `<category>` | <effect> | [repo-name](https://github.com/your-org/spec-kit-your-extension) |

(Table) Category — pick the one that best fits your extension:

• docs — reads, validates, or generates spec artifacts
• code — reviews, validates, or modifies source code
• process — orchestrates workflow across phases
• integration — syncs with external platforms
• visibility — reports on project health or progress

Effect — choose one:

• Read-only — produces reports without modifying files
• Read+Write — modifies files, creates artifacts, or updates specs

</details>



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[mnriem]

Please address Copilot feedback. If it is not applicable please explain why

[Copilot]

Pull request overview

Copilot reviewed 1 out of 1 changed files in this pull request and generated no new comments.

Comments suppressed due to low confidence (1)

extensions/EXTENSION-PUBLISHING-GUIDE.md:226

• The allowed Effect values are listed as plain text (Read-only, Read+Write) while Category values are code-formatted. Consider formatting the Effect values as code as well so it’s unambiguous that these are the exact strings to use in the README table.

- Read-only — produces reports without modifying files
- Read+Write — modifies files, creates artifacts, or updates specs

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[mnriem]

Thank you!