Fix exhaustive tabular CSV runs to queue directly from source

[Paul Lizer (paullizer)]

Summary:

• Bypass mini-agent paging for explicit exhaustive row-level CSV export/analysis requests when exactly one authorized CSV source is selected or uploaded.
• Build a replayable full-source query descriptor directly from the authorized blob, count rows through the bounded CSV replay path, and queue the existing durable runner for 300/3,000/30,000-row cases.
• Wire the direct queue path through mixed-source, legacy workspace-search, chat-upload, and streaming branches while preserving mini-agent fallback for unsupported sources.
• Add a regression test proving direct source-backed queueing works without prior filter_rows/query_tabular_data invocations.
• Bump app version to 0.250.133.

Log analysis:

• Captured App Service logs showed zero filter_rows/query_tabular_data/generated-output routing for the failed attempts, so the durable runner was never reached. This change moves exhaustive CSV requests ahead of that fragile dependency.

Validation:

• .\.venv\Scripts\python.exe -m py_compile application\single_app\route_backend_chats.py application\single_app\config.py functional_tests\test_tabular_row_orchestration_scale.py
• .\.venv\Scripts\python.exe functional_tests\test_tabular_row_orchestration_scale.py

[Paul Lizer (paullizer)]

Follow-up pushed after live log review:

• Removed local traceback imports that shadowed the module-level traceback import and masked the real streaming exception with cannot access local variable 'traceback'.
• Wrapped direct source-backed queueing so descriptor/credential failures log [TABULAR_GENERATED_OUTPUT] Direct source-backed generated output queueing skipped and fall back to existing tabular analysis instead of aborting the stream.
• Added regression coverage for non-fatal direct queue fallback.

Validation rerun:

• .\.venv\Scripts\python.exe -m py_compile application\single_app\route_backend_chats.py application\single_app\config.py functional_tests\test_tabular_row_orchestration_scale.py
• .\.venv\Scripts\python.exe functional_tests\test_tabular_row_orchestration_scale.py