[INS-402] Support custom endpoint configuration in Jira detectors

[mustansir14]

Description:

This PR adds support for custom endpoint configuration in the Jira V1 and V2 detectors by implementing the detectors.EndpointCustomizer and detectors.CloudProvider interfaces.

Checklist:

• Tests passing (make test-community)?
• Lint passing (make lint this requires golangci-lint)?

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Note

Medium Risk
Changes how Jira detectors choose domains for RawV2/verification by introducing configurable/cloud/found endpoint selection, which can alter detection/verification behavior and result counts. Risk is limited to Jira token scanning logic and is covered by expanded tests.

Overview
Jira token detectors (v1 and v2) now support endpoint customization by embedding EndpointSetter and implementing EndpointCustomizer/CloudProvider, including a default CloudEndpoint() of api.atlassian.com.

FromData no longer unconditionally falls back to api.atlassian.com when no domain is found; instead it builds the candidate domain set from found domains plus any configured endpoints and optional cloud endpoint, normalizing entries by stripping https:// and trailing /.

Tests were updated/expanded to exercise UseFoundEndpoints, UseCloudEndpoint, and configured endpoint combinations for both v1 and v2 (including integration tests enabling found endpoints).

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