Improve flow view UX and fix step naming

- Remove Fit All button, F key shortcut is sufficient
- Add right-click context menu with "Fit All (F)" option
- Add floating help banner that appears on focus and auto-hides
- Banner stays visible when mouse hovers over it
- Fix default step naming to increment per type (Code 1, Prompt 1, Code 2)
  instead of globally (Code 1, Prompt 2, Code 3)
- List view still shows overall step number (1, 2, 3) with per-type names

Co-Authored-By: Claude Opus 4.5 <[email protected]>

src/cmdforge/gui/pages/tool_builder_page.py

@@ -307,13 +307,19 @@ class ToolBuilderPage(QWidget):
         """Refresh steps list and flow view."""
         self.steps_list.clear()
         if self._tool and self._tool.steps:
+            # Count steps by type for default naming
+            prompt_count = 0
+            code_count = 0
+
             for i, step in enumerate(self._tool.steps, 1):
                 if isinstance(step, PromptStep):
-                    # Use custom name if set, otherwise default format
-                    step_name = step.name if step.name else f"Prompt {i}"
+                    prompt_count += 1
+                    # Use custom name if set, otherwise default per-type naming
+                    step_name = step.name if step.name else f"Prompt {prompt_count}"
                     text = f"{i}. {step_name} [{step.provider}] → ${step.output_var}"
                 elif isinstance(step, CodeStep):
-                    step_name = step.name if step.name else f"Code {i}"
+                    code_count += 1
+                    step_name = step.name if step.name else f"Code {code_count}"
                     text = f"{i}. {step_name} [python] → ${step.output_var}"
                 else:
                     text = f"{i}. Unknown step"