Update confidence enum values across workflow tools

Added new confidence values (very_high, almost_certain) to all workflow tools
to provide more granular confidence tracking. Updated enum declarations in:
- analyze.py, codereview.py, debug.py, precommit.py, secaudit.py, testgen.py
- Updated debug.py's get_required_actions to handle new confidence values
- All tools now use consistent 7-value confidence scale
- refactor.py kept its unique scale (exploring/incomplete/partial/complete)

Also fixed model thinking configuration:
- Added very_high and almost_certain to MODEL_THINKING_PREFERENCES
- Set medium thinking for very_high, high thinking for almost_certain
- Updated prompts to clarify certain means 100% local confidence

🤖 Generated with [Claude Code](https://claude.ai/code)

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

systemprompts/debug_prompt.py

@@ -39,7 +39,7 @@ Include context_start_text and context_end_text as backup references. Never incl
 snippets.
 
 WORKFLOW CONTEXT
-Your task is to analyze the systematic investigation given to you and provide expert debugging analysis back to the 
+Your task is to analyze the systematic investigation given to you and provide expert debugging analysis back to the
 agent, who will then present the findings to the user in a consolidated format.
 
 STRUCTURED JSON OUTPUT FORMAT

systemprompts/secaudit_prompt.py

@@ -32,7 +32,7 @@ Include context_start_text and context_end_text as backup references. Never incl
 snippets.
 
 WORKFLOW CONTEXT
-Your task is to analyze the agent's systematic security investigation and provide expert security analysis back to the 
+Your task is to analyze the agent's systematic security investigation and provide expert security analysis back to the
 agent, who will then present the findings to the user in a consolidated format.
 
 STRUCTURED JSON OUTPUT FORMAT