Add sample routines for hosted agents with various triggers

[howieleung]

Description

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[Copilot]

Pull request overview

Updates hosted-agent routine samples to self-provision temporary agent versions and adds GitHub issue trigger coverage.

Changes:

• Adds a GitHub issue-triggered routine sample.
• Makes existing routine samples create and clean up temporary hosted-agent versions.
• Documents required model and trigger configuration.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
sample_routines_with_timer_trigger.py	Self-provisions an agent for timer routines.
sample_routines_with_schedule_trigger.py	Self-provisions an agent for scheduled routines.
sample_routines_with_github_issue_trigger.py	Adds GitHub issue-triggered routine usage.
sample_routines_with_dispatch.py	Self-provisions an agent for dispatched routines.
sample_routines_crud.py	Self-provisions an agent for CRUD demonstrations.

Comments suppressed due to low confidence (3)

sdk/ai/azure-ai-projects/samples/hosted_agents/sample_routines_with_timer_trigger.py:74

• The temporary agent version is cleaned up when this context exits, but the routine is deleted only on the normal path. Any polling/service error or KeyboardInterrupt after creation leaves an enabled timer routine behind while restoring/deleting the agent version it was intended to invoke. Wrap the routine lifecycle in try/finally, as the schedule-trigger sample does, so the routine is deleted before this context unwinds.
  sdk/ai/azure-ai-projects/samples/hosted_agents/sample_routines_with_dispatch.py:79
• The temporary agent version is cleaned up when this context exits, but the routine is deleted only on the normal path. If dispatching or polling raises, the sample leaves a stale routine behind after restoring/deleting its backing agent version. Please protect the routine lifecycle with try/finally, matching the schedule-trigger sample's cleanup pattern.
  sdk/ai/azure-ai-projects/samples/hosted_agents/sample_routines_crud.py:72
• The new temporary hosted-agent context always removes/restores its version, but the routine cleanup remains normal-path only. If any CRUD call fails after creation, this leaves a routine referring to an agent whose temporary version has already been removed. Please place routine deletion in a finally block inside this context.