fix(search): use advanced search

[avivkeller]

cc @ovflowd - This PR reduces the amount of times the GH API is called significantly by using advanced search

[Copilot]

Pull Request Overview

This PR refactors the GitHub agenda issues functionality to use GitHub's advanced search API instead of iterating through all organization repositories individually. This change improves performance by making a single search query instead of multiple repository-specific queries.

• Switched from repository iteration to GitHub search API with advanced_search: true
• Updated data structure from array of repo objects to a key-value object mapping
• Removed unused parameters and simplified function signatures

Reviewed Changes

Copilot reviewed 4 out of 5 changed files in this pull request and generated 1 comment.

File	Description
src/github.mjs	Replaces repository iteration with GitHub search API and updates return type
src/meeting.mjs	Updates function signature and data processing to handle new object structure
src/constants.mjs	Adds constant for repository URL prefix length used in URL parsing
create-node-meeting-artifacts.mjs	Removes unused meetingConfig parameter from function call

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[avivkeller]

Bump @ovflowd

[ovflowd]

SGTM, but would love to have my comments replied at least :)