opamp: avoid enabling heartbeats after connection failure

[saichowdary007]

Description

Fixes #5053. Only run the OpAMP initial-state completion callback after a response was received successfully. Retry exhaustion and shutdown during backoff now leave heartbeat scheduling disabled.

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

• PYTHONPATH=src uvx --from uv==0.12.1 uv run --directory opamp/opentelemetry-opamp-client --with pytest --with pytest-vcr pytest tests/opamp/test_agent.py (22 passed)
• uvx ruff check and uvx ruff format --check on the changed files
• git diff --check

Does This PR Require a Core Repo Change?

• No.

Checklist

• Followed the style guidelines of this project
• Changelogs have been updated
• Unit tests have been added
• Documentation has been updated (not applicable)

AI assistance was used during implementation; the contributor reviewed the focused diff and test results and remains responsible for the contribution.

[linux-foundation-easycla]

• ❌ - login: @saichowdary007 / name: Saikumar Ch. The commit (05bf5bd, ac160ca, d2578f3) is not authorized under a signed CLA. Please click here to be authorized. For further assistance with EasyCLA, please visit our EasyCLA portal and chat with our support bot.
• ❌ - login: @saichowdary007 / name: saipakalapati. The commit (1277bb3, 7a99d39, 7f0ce5e, a0445a6, ac1da97, eebefcd, fb1df03, fb63cc2) is not authorized under a signed CLA. Please click here to be authorized. For further assistance with EasyCLA, please visit our EasyCLA portal and chat with our support bot.

[chatgpt-codex-connector]

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[opentelemetry-pr-dashboard]

Pull request dashboard status

Waiting on the author · refreshed 2026-10-04 00:14 UTC

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[opentelemetry-pr-dashboard]

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[lzchen]

@saichowdary007

Please sign the CLA.