feat(connector): add Calendly data-source connector

[abhinandan6123]

Description

Summary

Adds a Calendly data-source connector for cognee-community.

Features

• Personal Access Token authentication
• Ingests scheduled events and invitee context
• Includes invitee question-and-answer responses for searchable meeting context
• Supports event type selection
• Uses a min_start_time incremental sync window
• Emits hard-delete markers for cancelled/deleted events
• Includes package documentation and a runnable example

Implementation

The connector is added under:

packages/connector/calendly/

It follows the structure used by the existing community connectors and exposes:

from cognee_community_connector_calendly import calendly_source

Tests

4 passed

Covered:

• invitee question context ingestion
• incremental cursor behavior
• event type selection filtering
• cancelled event hard-delete handling

Validation

ruff check .
All checks passed!

pytest tests/ -v
4 passed

Closes #4816

DCO Affirmation

I affirm that all code in every commit of this pull request conforms to the terms of the Topoteretes Developer Certificate of Origin.