[Bug]: [extensions] specify extension search should query both core and community catalogs by default

[dhilipkumars]

Bug Description

Currently, the specify extension search (and add) command only queries the core catalog.json
by default. If a user wants to discover or install an extension from the community catalog (e.g. sync or retrospective), they have to manually override the catalog URL using an environment variable like this:

Steps to Reproduce

for searching community extension the user has to override with

export SPECKIT_CATALOG_URL="https://raw.githubusercontent.com/github/spec-kit/main/extensions/catalog.community.json"

Expected Behavior

Update Default URLs: Instead of a single DEFAULT_CATALOG_URL, define a list of default endpoints:

DEFAULT_CATALOG_URLS = [
    "https://raw.githubusercontent.com/github/spec-kit/main/extensions/catalog.json",
    "https://raw.githubusercontent.com/github/spec-kit/main/extensions/catalog.community.json"
]

Actual Behavior

actual behaviour only searches https://raw.githubusercontent.com/github/spec-kit/main/extensions/catalog.json and no community extensions are searched , this slight UX friction can be overcome with the proposal.

Specify CLI Version

0.1.13

AI Agent

Antigravity

Operating System

macbook

Python Version

Python 3.9.6

Error Logs

Additional Context

No response

[mnriem]

I have #1707 in flight for that?

[dhilipkumars]

addressed by #1707