fix: Trigger ad-hoc explorer index runs

[shruthilayaj]

The organizations:seer-run-mirror-explorer on SeerAgentClient.start_run meant
we weren't triggering the ad-hoc create explorer index tasks. This PR now calls the
index build tasks for explorer runs.

compute_delay was causing a circular import - so just moved that to a utils file

[sentry]

Bug: The compute_delay function can cause a ZeroDivisionError if called during a specific second of the hour, as the remaining time can become zero before the modulo operation.
_{Severity: MEDIUM}

Suggested Fix

Add a guard in compute_delay to handle cases where remaining.total_seconds() is zero or negative. For example, ensure the divisor for the modulo operation is at least 1. Using max(1, int(remaining.total_seconds())) as the divisor would prevent the division by zero.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's
not valid.

Location: src/sentry/tasks/utils.py#L33

Potential issue: The `compute_delay` function calculates a delay based on the time
remaining until the next hour. If the function is executed at a specific second (e.g.,
59 minutes and 43 seconds into the hour), the calculated `remaining` time can become
zero. This leads to a `ZeroDivisionError` during the modulo operation `... %
int(remaining.total_seconds())`. This pull request exposes the function to a new ad-hoc
call path triggered by user actions, making this edge case more likely. While the
exception is caught, it causes the associated explorer index tasks to silently fail to
dispatch.

Also affects:

• src/sentry/receivers/outbox/cell.py:293~297

_{Did we get this right? 👍 / 👎 to inform future reviews.}

[github-actions]

Backend Test Failures

Failures on a358d4b in this run:

tests/sentry/services/test_organization_actions.py::OrganizationUpdateWithOutboxTest::test_update_organization_with_outbox_message — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
src/sentry/testutils/cases.py:404: in _pre_setup
    super()._pre_setup()
src/sentry/utils/db.py:64: in _enter
    return original_enter(self)
           ^^^^^^^^^^^^^^^^^^^^
.venv/lib/python3.13/site-packages/django/db/transaction.py:211: in __enter__
    sid = connection.savepoint()
          ^^^^^^^^^^^^^^^^^^^^^^
.venv/lib/python3.13/site-packages/django/utils/asyncio.py:26: in inner
    return func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^
.venv/lib/python3.13/site-packages/django/db/backends/base/base.py:400: in savepoint
    self._savepoint(sid)
.venv/lib/python3.13/site-packages/django/db/backends/base/base.py:367: in _savepoint
    cursor.execute(self.ops.savepoint_create_sql(sid))
.venv/lib/python3.13/site-packages/django/db/backends/utils.py:122: in execute
    return super().execute(sql, params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.venv/lib/python3.13/site-packages/sentry_sdk/utils.py:1887: in runner
    return original_function(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.venv/lib/python3.13/site-packages/django/db/backends/utils.py:79: in execute
    return self._execute_with_wrappers(
.venv/lib/python3.13/site-packages/django/db/backends/utils.py:92: in _execute_with_wrappers
    return executor(sql, params, many, context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/sentry/db/postgres/base.py:70: in _execute__include_sql_in_error
    return execute(sql, params, many, context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/sentry/db/postgres/base.py:58: in _execute__clean_params
    return execute(sql, clean_bad_params(params), many, context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/sentry/testutils/hybrid_cloud.py:129: in __call__
    raise CrossTransactionAssertionError(
E   sentry.testutils.hybrid_cloud.CrossTransactionAssertionError: Transaction opened for db {'default'}, but command running against db control
E   SQL: SAVEPOINT "s140478049540992_x9047"

tests/sentry/tasks/test_options.py::SyncOptionsTest__InControlMode::test_task_persistent_name — log

[gw0] linux -- Python 3.13.1 /home/runner/work/sentry/sentry/.venv/bin/python3
src/sentry/testutils/cases.py:411: in _post_teardown
    super()._post_teardown()
.venv/lib/python3.13/site-packages/django/db/backends/postgresql/base.py:482: in check_constraints
    cursor.execute("SET CONSTRAINTS ALL IMMEDIATE")
.venv/lib/python3.13/site-packages/django/db/backends/utils.py:122: in execute
    return super().execute(sql, params)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.venv/lib/python3.13/site-packages/sentry_sdk/utils.py:1887: in runner
    return original_function(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
.venv/lib/python3.13/site-packages/django/db/backends/utils.py:79: in execute
    return self._execute_with_wrappers(
.venv/lib/python3.13/site-packages/django/db/backends/utils.py:92: in _execute_with_wrappers
    return executor(sql, params, many, context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/sentry/db/postgres/base.py:70: in _execute__include_sql_in_error
    return execute(sql, params, many, context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/sentry/db/postgres/base.py:58: in _execute__clean_params
    return execute(sql, clean_bad_params(params), many, context)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
src/sentry/testutils/hybrid_cloud.py:129: in __call__
    raise CrossTransactionAssertionError(
E   sentry.testutils.hybrid_cloud.CrossTransactionAssertionError: Transaction opened for db {'secondary'}, but command running against db control
E   SQL: SET CONSTRAINTS ALL IMMEDIATE