Remove dead export functions

[AshayK003]

Problem

Four functions are defined but never called from production code:

• save_markdown() in app/output/markdown.py
• save_pdf() in app/output/pdf.py
• render_executive() in app/output/markdown.py
• send_stream() in app/analyzers/llm_client.py

Only their own tests reference them. These are dead functions that add maintenance burden without providing value.

Impact

• ~120 lines of unused code
• Tests for dead code give false confidence
• Confuses contributors about intended architecture

Proposed Solution

Delete the four functions and their associated tests. If send_stream() was planned for future streaming support, it can be re-implemented when needed.

Acceptance Criteria

• Four functions removed
• Associated tests removed
• No broken imports

Testing Required

• Test: full test suite passes after removal

Files Affected

• app/output/markdown.py
• app/output/pdf.py
• app/analyzers/llm_client.py
• tests/test_markdown.py (update)
• tests/test_pdf.py (update)
• tests/test_llm_client.py (update)

Breaking Change

No — dead code removal.

Difficulty

Easy | Size: XS (30 minutes)