fix(gui): Resolve discussion compression error and improve entry tinting visibility

- Implement missing format_discussion in project_manager.py.
- Fix malformed escape characters in compression AI prompt.
- Ensure discussion compression updates the entry list in-place for immediate GUI refresh.
- Refactor discussion entry tinting using channels to draw backgrounds reliably behind text.
- Standardize Files & Media inventory layout and management buttons.

src/project_manager.py

@@ -49,6 +49,12 @@ def entry_to_str(entry: dict[str, Any]) -> str:
   return f"@{ts}\n{role}:\n{content}"
  return f"{role}:\n{content}"
 
+def format_discussion(entries: list[dict[str, Any]]) -> str:
+ """
+  Convert a list of discussion entry dicts into a single formatted string.
+ """
+ return "\n\n".join([entry_to_str(e) for e in entries])
+
 def str_to_entry(raw: str, roles: list[str]) -> dict[str, Any]:
  """