Fix context menu accessibility, conversation replies, and integrate polls into post details

This commit addresses several critical accessibility and functionality issues:

- Fix context menu keyboard shortcuts (Applications key and Shift+F10) in messages tab
- Resolve 404 errors when replying to private message conversations by implementing separate conversation reply handling
- Restore Enter key functionality for viewing post details
- Integrate poll voting into post details dialog as first tab instead of separate dialog
- Fix accessibility issues with poll display using QTextEdit and accessible list patterns
- Add comprehensive accessibility guidelines to CLAUDE.md covering widget choices, list patterns, and context menu support
- Update README.md with new features including context menu shortcuts, poll integration, and accessibility improvements

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

CLAUDE.md

@@ -14,6 +14,7 @@ Bifrost is a fully accessible fediverse client built with PySide6, designed spec
 2. **UI Event Handlers**: Avoid circular event chains (A triggers B which triggers A)
 3. **Timeline Operations**: Coordinate refresh calls and state changes to prevent conflicts
 4. **Lifecycle Events**: Ensure shutdown, close, and quit events don't overlap
+4. **Design**: Ensure  single point of truth is used as much as possible through out the code. This means functionality should not be duplicated across files.
 
 ### Required Patterns for Event-Heavy Operations
 
@@ -611,4 +612,82 @@ Examples of forbidden practices:
 - Shortened usernames or descriptions
 - Abbreviated profile information
 
-This document serves as the comprehensive development guide for Bifrost, ensuring all accessibility, functionality, and architectural decisions are preserved and can be referenced throughout development.
+### Screen Reader Accessibility Guidelines
+
+#### Widget Choice and Layout
+**DO:**
+- Use `QTextEdit` (read-only) for all text content that needs to be accessible
+- Use `QListWidget` with fake header items for navigable lists
+- Set proper `setAccessibleName()` on all interactive widgets
+- Enable keyboard navigation with `Qt.TextSelectableByKeyboard`
+
+**DON'T:**
+- Use `QLabel` for important information - screen readers often skip labels
+- Use disabled `QCheckBox` or `QRadioButton` widgets - they get skipped
+- Create single-item lists without fake headers - they're hard to navigate
+
+#### Accessible List Pattern
+For any list that users need to navigate (polls, favorites, boosts):
+```python
+list_widget = QListWidget()
+list_widget.setAccessibleName("Descriptive List Name")
+
+# Add fake header for single-item navigation
+fake_header = QListWidgetItem("List title:")
+fake_header.setFlags(Qt.ItemIsEnabled)  # Not selectable
+list_widget.addItem(fake_header)
+
+# Add actual items
+for item in items:
+    list_item = QListWidgetItem(item_text)
+    list_item.setData(Qt.UserRole, item_data)
+    list_widget.addItem(list_item)
+```
+
+#### Context Menu Accessibility
+**Required keyboard shortcuts for context menus:**
+- Applications key (`Qt.Key_Menu`)
+- Shift+F10 (`Qt.Key_F10` with `Qt.ShiftModifier`)
+
+Both must trigger: `self.customContextMenuRequested.emit(center)`
+
+#### Interactive vs Display Content
+**For expired/completed interactive elements (polls, forms):**
+- Replace disabled controls with accessible display lists
+- Show results using the accessible list pattern
+- Never leave users with disabled widgets they can't interact with
+
+**For live interactive elements:**
+- Use standard Qt controls (`QCheckBox`, `QRadioButton`, `QPushButton`)
+- Ensure all controls have meaningful `setAccessibleName()`
+- Provide clear feedback for actions
+
+#### Information Display Priority
+**All important information must be in accessible widgets:**
+1. **Primary location:** `QTextEdit` (read-only, keyboard selectable)
+2. **Secondary location:** `QListWidget` items
+3. **Never primary:** `QLabel` widgets (often skipped)
+
+**Example of accessible content display:**
+```python
+content_text = QTextEdit()
+content_text.setAccessibleName("Full Post Details")
+content_text.setPlainText(f"Author: @{username}\n\nContent:\n{post_content}\n\nMetadata:\n{details}")
+content_text.setReadOnly(True)
+content_text.setTextInteractionFlags(Qt.TextSelectableByKeyboard | Qt.TextSelectableByMouse)
+```
+
+#### Dialog and Tab Design
+**Avoid content duplication:**
+- Don't show the same information in multiple places
+- Use tabs to organize different types of information
+- Keep essential stats/counts at the top level
+- Put detailed content in dedicated tabs
+
+**Tab organization example:**
+- Statistics: Brief counts at dialog top
+- Poll tab: Interactive voting or accessible results list
+- Content tab: Full post details in accessible text widget
+- Interaction tabs: Who favorited/boosted in accessible lists
+
+This document serves as the comprehensive development guide for Bifrost, ensuring all accessibility, functionality, and architectural decisions are preserved and can be referenced throughout development.