Implement smart notification filtering to reduce notification fatigue

[Helmi]

Description

Currently ccnotify sends notifications for every bash command execution, causing significant notification fatigue. The current logic at notify.py:768 states "Notify for all Bash commands" which defeats the purpose of an intelligent notification system.

Context

• Project area: Core notification filtering logic in src/ccnotify/notify.py:756-884
• Complexity assessment: 5/10 (moderate logic changes, path analysis needed)
• Current behavior: All bash commands trigger notifications
• Problem: Notification fatigue from routine operations like ls, cat, pwd, echo, etc.

Technical Details

Affected files:

• src/ccnotify/notify.py:756-884 - Main PreToolUse filtering logic that needs modification
• Potentially config system for customizable command whitelist

Current filtering logic:

# Lines 762-863: Currently notifies for ALL bash commands
if tool_name == "Bash":
    # Notify for all Bash commands  <- THIS IS THE PROBLEM

Requirements

Core Approach: Minimal Whitelist + Path-Based Filtering

1. Minimal whitelist approach - Only truly dangerous commands should trigger notifications:

   • rm, sudo, chmod, chown, mv (file operations with potential for damage)
   • Exclude routine commands: ls, cat, pwd, echo, grep, find, git status, etc.
   • Exclude even moderately risky but common commands: cp, curl, wget, docker

2. Path-based filtering - Commands targeting files outside the current project directory should trigger notifications regardless of command type

3. Simplicity - Keep the logic straightforward and predictable

Implementation Steps

• Create minimal dangerous command whitelist in filtering logic
• Implement path analysis to detect when commands target files outside project directory
• Modify PreToolUse handler filtering logic (notify.py:762-863)
• Add configuration option for customizable whitelist (optional enhancement)
• CRITICAL: Local testing - Test extensively with real Claude Code usage before any commit
• Update any relevant documentation about filtering behavior

Acceptance Criteria

• Only dangerous commands (rm, sudo, chmod, chown, mv) trigger notifications by default
• Commands targeting files outside current project directory trigger notifications
• Significant reduction in notification volume during typical Claude Code sessions
• Local testing demonstrates proper filtering without missing important events
• All existing tests pass
• No false negatives for truly dangerous operations

Testing Requirements

MUST complete local testing before any GitHub push:

• Test with typical Claude Code development sessions
• Verify dangerous commands still trigger notifications
• Verify routine commands are filtered out
• Test path-based filtering with commands targeting system files
• Measure notification volume reduction