Refine coding standards and testing guidelines

- Updated coding rule descriptions for clarity and emphasis on readability, meaningful comments, and test verification.
- Adjusted thresholds for test coverage on business logic from 80% to 75%, aligning with the canonical reference in `cursor-meta.mdc`.
- Enhanced guidelines for handling skipped tests, emphasizing the need for investigation and classification.
- Introduced completeness audit requirements for research decomposition to ensure thoroughness in addressing problem dimensions.

.cursor/rules/human-attention-sound.mdc

@@ -4,21 +4,43 @@ alwaysApply: true
 ---
 # Sound Notification on Human Input
 
-Whenever you are about to ask the user a question, request confirmation, present options for a decision, or otherwise pause and wait for human input, you MUST first run the appropriate shell command for the current OS:
+## Sound commands per OS
+
+Detect the OS from user system info or `uname -s`:
 
 - **macOS**: `afplay /System/Library/Sounds/Glass.aiff &`
 - **Linux**: `paplay /usr/share/sounds/freedesktop/stereo/bell.oga 2>/dev/null || aplay /usr/share/sounds/freedesktop/stereo/bell.oga 2>/dev/null || echo -e '\a' &`
 - **Windows (PowerShell)**: `[System.Media.SystemSounds]::Exclamation.Play()`
 
-Detect the OS from the user's system info or by running `uname -s` if unknown.
+## When to play (play exactly once per trigger)
 
-This applies to:
-- Asking clarifying questions
-- Presenting choices (e.g. via AskQuestion tool)
-- Requesting approval for destructive actions
-- Reporting that you are blocked and need guidance
-- Any situation where the conversation will stall without user response
-- Completing a task (final answer / deliverable ready for review)
+Play the sound when your turn will end in one of these states:
 
-Do NOT play the sound when:
-- You are in the middle of executing a multi-step task and just providing a status update
+1. You are about to call the AskQuestion tool — sound BEFORE the AskQuestion call
+2. Your text ends with a direct question to the user that cannot be answered without their input (e.g., "Which option do you prefer?", "What is the database name?", "Confirm before I push?")
+3. You are reporting that you are BLOCKED and cannot continue without user input (missing credentials, conflicting requirements, external approval required)
+4. You have just completed a destructive or irreversible action the user asked to review (commit, push, deploy, data migration, file deletion)
+
+## When NOT to play
+
+- You are mid-execution and returning a progress update (the conversation is not stalling)
+- You are answering a purely informational or factual question and no follow-up is required
+- You have already played the sound once this turn for the same pause point
+- Your response only contains text describing what you did or found, with no question, no block, no irreversible action
+
+## "Trivial" definition
+
+A response is trivial (no sound) when ALL of the following are true:
+- No explicit question to the user
+- No "I am blocked" report
+- No destructive/irreversible action that needs review
+
+If any one of those is present, the response is non-trivial — play the sound.
+
+## Ordering
+
+The sound command is a normal Shell tool call. Place it:
+- **Immediately before an AskQuestion tool call** in the same message, or
+- **As the last Shell call of the turn** if ending with a text-based question, block report, or post-destructive-action review
+
+Do not play the sound as part of routine command execution — only at the pause points listed under "When to play".