docs: Add SPEC-23 Gradio 6.0 Modernization Audit

Identifies missing Gradio 6.0 best practices:
- fill_height=True (chat fills vertical space)
- autoscroll=True (auto-scroll during streaming)
- type="messages" (OpenAI-style format - evaluate separately)
- show_progress="full" (per SPEC-22)

Async agent can implement after SPEC-22.

docs/specs/SPEC-23-GRADIO-MODERNIZATION.md

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+# SPEC-23: Gradio 6.0 Modernization Audit
+
+**Status:** READY FOR IMPLEMENTATION
+**Priority:** P3 (Technical alignment)
+**Effort:** 30 minutes
+**Dependencies:** SPEC-22 (Progress Bar Removal)
+
+---
+
+## Executive Summary
+
+Audit of `src/app.py` against Gradio 6.0.1 best practices. Identifies parameters we should add or update for full alignment with modern Gradio.
+
+---
+
+## Current State vs Best Practices
+
+| Feature | Current | Best Practice | Action |
+|---------|---------|---------------|--------|
+| `type` param | Not set (legacy) | `type="messages"` | **ADD** - Uses OpenAI-style message format |
+| `fill_height` | Not set | `fill_height=True` | **ADD** - Chat fills vertical space |
+| `autoscroll` | Not set | `autoscroll=True` | **ADD** - Auto-scroll to latest message |
+| `show_progress` | Not set (minimal) | `show_progress="full"` | **ADD** - Per SPEC-22 |
+| `gr.Progress` | Used (broken) | Remove | **REMOVE** - Per SPEC-22 |
+
+---
+
+## Detailed Findings
+
+### 1. Message Format (`type="messages"`)
+
+**Current:** Not specified (uses legacy tuple format)
+**Recommended:** `type="messages"`
+
+The `type="messages"` format uses OpenAI-style dictionaries:
+```python
+{"role": "user" | "assistant", "content": str}
+```
+
+This is the modern standard and aligns with our LLM backends.
+
+**Note:** This may require updating how we handle `history` parameter.
+
+### 2. Fill Height (`fill_height=True`)
+
+**Current:** Not set
+**Recommended:** `fill_height=True`
+
+Makes the chat interface fill available vertical space. Better UX on larger screens.
+
+**Known Issue:** [GitHub #10407](https://github.com/gradio-app/gradio/issues/10407) - May conflict with `save_history=True`. We don't use `save_history`, so should be fine.
+
+### 3. Autoscroll (`autoscroll=True`)
+
+**Current:** Not set
+**Recommended:** `autoscroll=True`
+
+Ensures chat auto-scrolls to the latest message during streaming. Critical for long research outputs.
+
+---
+
+## Implementation Checklist
+
+### SPEC-22 Items (Do First)
+- [ ] Remove `progress: gr.Progress = gr.Progress()` from `research_agent` signature
+- [ ] Remove all `progress(...)` calls in `research_agent`
+
+### SPEC-23 Items
+- [ ] Add `show_progress="full"` to `gr.ChatInterface`
+- [ ] Add `fill_height=True` to `gr.ChatInterface`
+- [ ] Add `autoscroll=True` to `gr.ChatInterface`
+- [ ] Evaluate `type="messages"` migration (may require history format changes)
+
+---
+
+## Code Changes
+
+### Before (Current)
+```python
+demo = gr.ChatInterface(
+    fn=research_agent,
+    title="🍆 DeepBoner",
+    description=description,
+    examples=[...],
+    cache_examples=False,
+    run_examples_on_click=False,
+    additional_inputs_accordion=additional_inputs_accordion,
+    additional_inputs=[...],
+)
+```
+
+### After (Modernized)
+```python
+demo = gr.ChatInterface(
+    fn=research_agent,
+    title="🍆 DeepBoner",
+    description=description,
+    examples=[...],
+    cache_examples=False,
+    run_examples_on_click=False,
+    additional_inputs_accordion=additional_inputs_accordion,
+    additional_inputs=[...],
+    # SPEC-22: Use native progress instead of gr.Progress
+    show_progress="full",
+    # SPEC-23: Modern Gradio 6.0 settings
+    fill_height=True,
+    autoscroll=True,
+    # NOTE: type="messages" requires history format migration - evaluate separately
+)
+```
+
+---
+
+## Risk Assessment
+
+| Change | Risk | Mitigation |
+|--------|------|------------|
+| `show_progress="full"` | Low | Native Gradio feature |
+| `fill_height=True` | Low | May affect layout, test visually |
+| `autoscroll=True` | Low | Native feature, improves UX |
+| `type="messages"` | Medium | Requires history format changes - defer if needed |
+
+---
+
+## Verification
+
+```bash
+# After changes
+make check
+
+# Manual test
+uv run python src/app.py
+# Verify:
+# 1. Chat fills vertical space
+# 2. Auto-scrolls during streaming
+# 3. Spinner appears (not floating progress bar)
+```
+
+---
+
+## References
+
+- [Gradio ChatInterface Docs](https://www.gradio.app/docs/gradio/chatinterface)
+- [GitHub #10407: fill_height with save_history](https://github.com/gradio-app/gradio/issues/10407)
+- [GitHub #11109: Autoscroll issue](https://github.com/gradio-app/gradio/issues/11109)