Update doc about token and samples

[MarcoZama]

Update doc about directline request token and usage.
I made a PR for the connector sample

[learn-build-service-prod]

Learn Build status updates of commit f185709:

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[learn-build-service-prod]

Learn Build status updates of commit 04c2176:

❌ Validation status: errors

Please follow instructions here which may help to resolve issue.

File	Status	Preview URL	Details
	❌Error		Details

• [Error: CannotMergeCommit] Cannot merge commit 04c21764cd672cabdfa7360334833462c11f43d3 in branch zamana-get-directline-token of repository https://github.com/MarcoZama/power-platform into branch main (commit c1a7f5c06c692679d04c4c33e8fc3b1ff7561975). Please follow this documentation: https://help.github.com/articles/resolving-a-merge-conflict-using-the-command-line/ to use git.exe to resolve you content conflicts locally and then push to remote.

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[learn-build-service-prod]

Learn Build status updates of commit 2b19446:

✅ Validation status: passed

File	Status	Preview URL	Details
power-virtual-agents/publication-connect-bot-to-custom-application.md	✅Succeeded

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel