Add tool enable/disable and auto-discovery of function names

[BillJr99]

Summary

This PR adds the ability to enable/disable individual tools in provider configurations and implements automatic discovery of available function/tool names from code blocks and package introspection. Tools can now be toggled on/off without losing their schema, and the UI provides smart dropdowns for selecting function names when available.

Key Changes

Tool Enable/Disable Feature

• Added enabled field to tool specs (defaults to true when missing)
• Tools with enabled: false are kept in YAML but not registered with MCP or advertised to the LLM
• UI includes a toggle switch in each tool card header to enable/disable tools
• Disabled tools are visually de-emphasized with reduced opacity and a "disabled" badge
• Both _provider_to_structured() and _structured_to_yaml() now handle the enabled field

Tool Name Prefixing & Normalization

• Implemented normalize_provider_name() to convert provider names to MCP-safe identifiers ([a-zA-Z0-9-])
• Implemented advertised_tool_name() to create namespaced tool names: <provider>__<tool>
• Updated register_tool() to accept an optional advertised_name parameter for prefixed registration
• Updated register_provider() to skip disabled tools and register enabled tools with prefixed names
• Built-in tools now use the __ separator: mcpproxy__listfiles and mcpproxy__getfile

Auto-Discovery of Function Names

• Added discoverFunctions() JS function that:
  • For code providers: parses the code block to extract async def function names
  • For package providers: introspects the command via /api/introspect to get available tools
  • Updates knownFunctions array and displays discovery status
• Added /api/extract-functions endpoint to parse Python code and extract function definitions
• Function/tool name fields now render as a dropdown + text input combo when names are known
• Dropdown includes discovered names plus an "Other…" option for custom values
• Discovery runs automatically when:
  • A provider is opened
  • Code changes (debounced 300ms)
  • Package command field loses focus
  • User clicks the new "↻ Re-scan" button
• Failure is silent — UI gracefully falls back to free-form text input

UI Improvements

• Replaced manual "🔍 Introspect Tools" and "🔍 Analyze Functions" buttons with auto-discovery
• Added "↻ Re-scan" button to manually trigger discovery
• Added discovery status indicator showing "Analyzing code…", "Introspecting package…", or results
• Function/tool name picker uses a new .fn-pick-row layout with dropdown + input
• Added visual styling for disabled tools (.badge-disabled, .tool-card.disabled)
• Added form styling for checkboxes (.form-check-input)
• Wizard now auto-introspects on "Next" button click instead of requiring manual action

Wizard Improvements

• Package wizard auto-introspects when advancing to the next step
• Code wizard provides live function detection as user types
• Both use debounced analysis to avoid excessive processing

Testing

• Added comprehensive tests for normalize_provider_name(), advertised_tool_name(), and tool_is_enabled()
• Added tests for register_provider() prefixing and disabled tool filtering
• Updated existing tests to expect the new enabled field in tool specs
• Updated test assertions to use the new __ separator in tool names

Notable Implementation Details

• The enabled field is always written explicitly to YAML (never omitted) for clarity
• Missing enabled field in existing YAML defaults to true for backward compatibility
• Tool names in YAML remain unprefixed; the prefix is added only when registering with MCP
• Discovery status is stored in module-level JS variables (knownFunctions, knownFnStatus, knownFnMessage)
• Dropdown selection is kept in sync with text input via _syncFnPick() as user types
• Disabled tools are skipped during registration without attempting to load their handlers

https://claude.ai/code/session_01KRZQTKxffN7toaSDh71D6e