Update media-server: Add execution timing and improve script/callback execution UI

Backend improvements:
- Add execution_time tracking for script execution
- Add execution_time tracking for callback execution
- Add /api/callbacks/execute/{callback_name} endpoint for debugging callbacks

Frontend improvements:
- Fix duration display showing N/A for fast scripts (0 is falsy in JS)
- Increase duration precision to 3 decimal places (0.001s)
- Always show output section with "(no output)" message when empty
- Improve output formatting with italic gray text for empty output

Documentation:
- Add localization section to README
- Document available languages (English, Russian)
- Add guide for contributing new translations

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

media_server/routes/callbacks.py

@@ -1,7 +1,10 @@
 """Callback management API endpoints."""
 
+import asyncio
 import logging
 import re
+import subprocess
+import time
 from typing import Any
 
 from fastapi import APIRouter, Depends, HTTPException, status
@@ -34,6 +37,18 @@ class CallbackCreateRequest(BaseModel):
     shell: bool = Field(default=True, description="Run command in shell")
 
 
+class CallbackExecuteResponse(BaseModel):
+    """Response model for callback execution."""
+
+    success: bool
+    callback: str
+    exit_code: int | None = None
+    stdout: str = ""
+    stderr: str = ""
+    error: str | None = None
+    execution_time: float | None = None
+
+
 def _validate_callback_name(name: str) -> None:
     """Validate callback name.
 
@@ -84,6 +99,116 @@ async def list_callbacks(_: str = Depends(verify_token)) -> list[CallbackInfo]:
     ]
 
 
+@router.post("/execute/{callback_name}")
+async def execute_callback(
+    callback_name: str,
+    _: str = Depends(verify_token),
+) -> CallbackExecuteResponse:
+    """Execute a callback for debugging purposes.
+
+    Args:
+        callback_name: Name of the callback to execute
+
+    Returns:
+        Execution result including stdout, stderr, and exit code
+    """
+    # Validate callback name
+    _validate_callback_name(callback_name)
+
+    # Check if callback exists
+    if callback_name not in settings.callbacks:
+        raise HTTPException(
+            status_code=status.HTTP_404_NOT_FOUND,
+            detail=f"Callback '{callback_name}' not found. Use /api/callbacks/list to see configured callbacks.",
+        )
+
+    callback_config = settings.callbacks[callback_name]
+
+    logger.info(f"Executing callback for debugging: {callback_name}")
+
+    try:
+        # Execute in thread pool to not block
+        loop = asyncio.get_event_loop()
+        result = await loop.run_in_executor(
+            None,
+            lambda: _run_callback(
+                command=callback_config.command,
+                timeout=callback_config.timeout,
+                shell=callback_config.shell,
+                working_dir=callback_config.working_dir,
+            ),
+        )
+
+        return CallbackExecuteResponse(
+            success=result["exit_code"] == 0,
+            callback=callback_name,
+            exit_code=result["exit_code"],
+            stdout=result["stdout"],
+            stderr=result["stderr"],
+            execution_time=result.get("execution_time"),
+        )
+
+    except Exception as e:
+        logger.error(f"Callback execution error: {e}")
+        return CallbackExecuteResponse(
+            success=False,
+            callback=callback_name,
+            error=str(e),
+        )
+
+
+def _run_callback(
+    command: str,
+    timeout: int,
+    shell: bool,
+    working_dir: str | None,
+) -> dict[str, Any]:
+    """Run a callback synchronously.
+
+    Args:
+        command: Command to execute
+        timeout: Timeout in seconds
+        shell: Whether to run in shell
+        working_dir: Working directory
+
+    Returns:
+        Dict with exit_code, stdout, stderr, execution_time
+    """
+    start_time = time.time()
+    try:
+        result = subprocess.run(
+            command,
+            shell=shell,
+            cwd=working_dir,
+            capture_output=True,
+            text=True,
+            timeout=timeout,
+        )
+        execution_time = time.time() - start_time
+        return {
+            "exit_code": result.returncode,
+            "stdout": result.stdout[:10000],  # Limit output size
+            "stderr": result.stderr[:10000],
+            "execution_time": execution_time,
+        }
+    except subprocess.TimeoutExpired:
+        execution_time = time.time() - start_time
+        return {
+            "exit_code": -1,
+            "stdout": "",
+            "stderr": f"Callback timed out after {timeout} seconds",
+            "execution_time": execution_time,
+        }
+    except Exception as e:
+        execution_time = time.time() - start_time
+        return {
+            "exit_code": -1,
+            "stdout": "",
+            "stderr": str(e),
+            "execution_time": execution_time,
+        }
+
+
 @router.post("/create/{callback_name}")
 async def create_callback(
     callback_name: str,

media_server/routes/scripts.py

@@ -4,6 +4,7 @@ import asyncio
 import logging
 import re
 import subprocess
+import time
 from typing import Any
 
 from fastapi import APIRouter, Depends, HTTPException, status
@@ -33,6 +34,7 @@ class ScriptExecuteResponse(BaseModel):
     stdout: str = ""
     stderr: str = ""
     error: str | None = None
+    execution_time: float | None = None
 
 
 class ScriptInfo(BaseModel):
@@ -117,6 +119,7 @@ async def execute_script(
             exit_code=result["exit_code"],
             stdout=result["stdout"],
             stderr=result["stderr"],
+            execution_time=result.get("execution_time"),
         )
 
     except Exception as e:
@@ -143,8 +146,9 @@ def _run_script(
         working_dir: Working directory
 
     Returns:
-        Dict with exit_code, stdout, stderr
+        Dict with exit_code, stdout, stderr, execution_time
     """
+    start_time = time.time()
     try:
         result = subprocess.run(
             command,
@@ -154,22 +158,28 @@ def _run_script(
             text=True,
             timeout=timeout,
         )
+        execution_time = time.time() - start_time
         return {
             "exit_code": result.returncode,
             "stdout": result.stdout[:10000],  # Limit output size
             "stderr": result.stderr[:10000],
+            "execution_time": execution_time,
         }
     except subprocess.TimeoutExpired:
+        execution_time = time.time() - start_time
         return {
             "exit_code": -1,
             "stdout": "",
             "stderr": f"Script timed out after {timeout} seconds",
+            "execution_time": execution_time,
         }
     except Exception as e:
+        execution_time = time.time() - start_time
         return {
             "exit_code": -1,
             "stdout": "",
             "stderr": str(e),
+            "execution_time": execution_time,
         }