fix: replace_in_file tool consistently failing with Claude 4 Sonnet due to a few specific quirks (RooCodeInc#3757)

Author: saoudrizwan

src/core/prompts/system.ts

@@ -604,6 +604,7 @@ RULES
 - Before executing commands, check the "Actively Running Terminals" section in environment_details. If present, consider how these active processes might impact your task. For example, if a local development server is already running, you wouldn't need to start it again. If no active terminals are listed, proceed with command execution as normal.
 - When using the replace_in_file tool, you must include complete lines in your SEARCH blocks, not partial lines. The system requires exact line matches and cannot match partial lines. For example, if you want to match a line containing "const x = 5;", your SEARCH block must include the entire line, not just "x = 5" or other fragments.
 - When using the replace_in_file tool, if you use multiple SEARCH/REPLACE blocks, list them in the order they appear in the file. For example if you need to make changes to both line 10 and line 50, first include the SEARCH/REPLACE block for line 10, followed by the SEARCH/REPLACE block for line 50.
+- When using the replace_in_file tool, Do NOT add extra characters to the markers (e.g., <<<<<<< SEARCH> is INVALID). Do NOT forget to use the closing >>>>>>> REPLACE marker. Do NOT modify the marker format in any way. Malformed XML will cause complete tool failure and break the entire editing process.
 - It is critical you wait for the user's response after each tool use, in order to confirm the success of the tool use. For example, if asked to make a todo app, you would create a file, wait for the user's response it was created successfully, then create another file if needed, wait for the user's response it was created successfully, etc.${
 	supportsBrowserUse
 		? " Then if you want to test your work, you might use browser_action to launch the site, wait for the user's response confirming the site was launched along with a screenshot, then perhaps e.g., click a button to test functionality if needed, wait for the user's response confirming the button was clicked along with a screenshot of the new state, before finally closing the browser."