Add AI persona profiles for prompt injection

Profiles allow users to inject system instructions into prompts,
customizing the AI's behavior and persona for tool execution.

Features:
- Profile dataclass with name, description, system_prompt
- 8 built-in profiles: None, Comedian, Technical Writer, Teacher,
  Concise, Creative, Code Reviewer, Analyst
- Custom profile creation and storage in ~/.cmdforge/profiles/
- Profile selector in Prompt Step dialog
- Profile injection during tool execution
- Profiles page in GUI (Ctrl+4) for viewing and managing profiles

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

src/cmdforge/gui/dialogs/step_dialog.py

@@ -5,9 +5,11 @@ from PySide6.QtWidgets import (
     QComboBox, QPushButton, QHBoxLayout, QLabel,
     QPlainTextEdit
 )
+from PySide6.QtCore import Qt
 
 from ...tool import PromptStep, CodeStep
 from ...providers import load_providers
+from ...profiles import list_profiles
 
 
 class PromptStepDialog(QDialog):
@@ -43,6 +45,16 @@ class PromptStepDialog(QDialog):
                 self.provider_combo.addItem(default)
         form.addRow("Provider:", self.provider_combo)
 
+        # Profile selection
+        self.profile_combo = QComboBox()
+        profiles = list_profiles()
+        for profile in profiles:
+            self.profile_combo.addItem(profile.name)
+            # Set tooltip with description
+            idx = self.profile_combo.count() - 1
+            self.profile_combo.setItemData(idx, profile.description, Qt.ToolTipRole)
+        form.addRow("Profile:", self.profile_combo)
+
         # Output variable
         self.output_input = QLineEdit()
         self.output_input.setPlaceholderText("response")
@@ -87,6 +99,12 @@ class PromptStepDialog(QDialog):
         else:
             self.provider_combo.setCurrentText(step.provider)
 
+        # Load profile
+        if step.profile:
+            idx = self.profile_combo.findText(step.profile)
+            if idx >= 0:
+                self.profile_combo.setCurrentIndex(idx)
+
         self.output_input.setText(step.output_var)
         self.prompt_input.setPlainText(step.prompt)
 
@@ -106,10 +124,15 @@ class PromptStepDialog(QDialog):
 
     def get_step(self) -> PromptStep:
         """Get the step from form data."""
+        profile = self.profile_combo.currentText()
+        # Don't store "None" profile
+        if profile == "None":
+            profile = None
         return PromptStep(
             prompt=self.prompt_input.toPlainText(),
             provider=self.provider_combo.currentText(),
-            output_var=self.output_input.text().strip()
+            output_var=self.output_input.text().strip(),
+            profile=profile
         )