What problem does this PR solve?

This pull request introduces a new CoordinatorContext class to better manage query coordination and runtime states across BE (Backend) nodes, separating responsibilities from QueryContext. The changes refactor how runtime filter merge controllers and query coordination are handled, improve resource cleanup, and enhance debugging capabilities. The most important changes are grouped below.

Introduction of CoordinatorContext

• Added new CoordinatorContext class (coordinator_context.h, coordinator_context.cpp) to manage query coordination and runtime states beyond the lifecycle of QueryContext. This class holds references to runtime filter merge controllers and resource contexts, and provides debug and timeout management functions. ([[1]](https://github.com/apache/doris/pull/58189/files#diff-789e0272245b8bd410068d5444860ea98a102ff4ce756f48217d7df53ebd4abfR1-R114), [[2]](https://github.com/apache/doris/pull/58189/files#diff-6839f3ffba20c6a2e7c6727e45c07be21838302c33e196007e8dde8d29b0dd75R1-R94))

Refactoring Query and Coordinator Context Usage

• Refactored FragmentMgr to create and manage CoordinatorContext instances per query, storing them in _coordinator_context_map, and linking them to their respective QueryContext objects. ([[1]](https://github.com/apache/doris/pull/58189/files#diff-3be0bcdb0c3c5fe6415556cf49c7270d4fc2e2f071c0240145ce175a32a484e2R731-R734), [[2]](https://github.com/apache/doris/pull/58189/files#diff-9f558888989dd08ae617466466716e106c8480524f9f1d86d7b0b650115058a1R213-R214))
• Updated runtime filter merge controller handling to be managed by CoordinatorContext instead of QueryContext, ensuring proper lifecycle and avoiding circular references. ([[1]](https://github.com/apache/doris/pull/58189/files#diff-3be0bcdb0c3c5fe6415556cf49c7270d4fc2e2f071c0240145ce175a32a484e2L758-R763), [[2]](https://github.com/apache/doris/pull/58189/files#diff-3be0bcdb0c3c5fe6415556cf49c7270d4fc2e2f071c0240145ce175a32a484e2L1314-R1336), [[3]](https://github.com/apache/doris/pull/58189/files#diff-3be0bcdb0c3c5fe6415556cf49c7270d4fc2e2f071c0240145ce175a32a484e2L1351-R1377))

Resource Cleanup and Timeout Management

• Ensured that CoordinatorContext objects are erased from _coordinator_context_map when a query is cancelled, and added logic to detect and log lingering contexts that have timed out. ([[1]](https://github.com/apache/doris/pull/58189/files#diff-3be0bcdb0c3c5fe6415556cf49c7270d4fc2e2f071c0240145ce175a32a484e2R911), [[2]](https://github.com/apache/doris/pull/58189/files#diff-3be0bcdb0c3c5fe6415556cf49c7270d4fc2e2f071c0240145ce175a32a484e2R973-R986))

Debugging and Monitoring Improvements

• Enhanced pipeline task dumping to include CoordinatorContext debug information for better observability of query coordination states. ([[1]](https://github.com/apache/doris/pull/58189/files#diff-3be0bcdb0c3c5fe6415556cf49c7270d4fc2e2f071c0240145ce175a32a484e2R793-R802), [[2]](https://github.com/apache/doris/pull/58189/files#diff-3be0bcdb0c3c5fe6415556cf49c7270d4fc2e2f071c0240145ce175a32a484e2L807-L813))

Minor Code Cleanups

• Removed unused includes and variables from query_context.cpp and updated method signatures for clarity and consistency. ([[1]](https://github.com/apache/doris/pull/58189/files#diff-cde85080314c53bf67ef65f4257c3545119819c3534d4412910f1677ce217c3aL26), [[2]](https://github.com/apache/doris/pull/58189/files#diff-cde85080314c53bf67ef65f4257c3545119819c3534d4412910f1677ce217c3aL35), [[3]](https://github.com/apache/doris/pull/58189/files#diff-cde85080314c53bf67ef65f4257c3545119819c3534d4412910f1677ce217c3aL46-L49), [[4]](https://github.com/apache/doris/pull/58189/files#diff-cde85080314c53bf67ef65f4257c3545119819c3534d4412910f1677ce217c3aL95-L112), [[5]](https://github.com/apache/doris/pull/58189/files#diff-96a1dcbd297bc02611e5cdcfb8ebcdbde45c2603f22fb3454c0da1c7ec56261aL198-R204), [[6]](https://github.com/apache/doris/pull/58189/files#diff-3be0bcdb0c3c5fe6415556cf49c7270d4fc2e2f071c0240145ce175a32a484e2R67), [[7]](https://github.com/apache/doris/pull/58189/files#diff-3be0bcdb0c3c5fe6415556cf49c7270d4fc2e2f071c0240145ce175a32a484e2L78), [[8]](https://github.com/apache/doris/pull/58189/files#diff-9f558888989dd08ae617466466716e106c8480524f9f1d86d7b0b650115058a1R56))

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label