docs(ai): update built-in functions list to match implementation

Updated AI prompt to only list LISP functions that are actually implemented:

Removed misleading tools:
- ❌ MAP, FILTER, SUM, AVG (MCP tools, not built-ins)
- ❌ GUARD, ERROR, INPUT (not implemented)
- ❌ MAX, MIN, ABS, SQRT, POW, ROUND (not implemented)
- ❌ MEAN, MEDIAN, STDDEV, etc. (MCP tools, not built-ins)

Added accurate list:
- ✅ LISP Forms: define, const, set!, if, while, for, do, when
- ✅ Logic: not, null?, empty?
- ✅ Arrays: length, last, range
- ✅ Utilities: now, log
- ✅ Note: MCP tools like COUNT, APPEND listed separately

This prevents AI from using non-existent functions.

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

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

Author: 0xrinegade

src/services/ai_service.rs

@@ -678,12 +678,13 @@ Conditional Logic:
           "B"
           "C"))
 
-# Essential Built-in Tools
+# Essential Built-in Functions
 
-**Data Manipulation**: MAP, FILTER, SUM, AVG, COUNT, FLATTEN, APPEND, FIND, SORT
-**Statistics**: MEAN, MEDIAN, STDDEV, T_TEST, CORRELATE, PERCENTILE
-**Math**: ABS, SQRT, POW, ROUND, MAX, MIN
-**Utilities**: NOW, LOG, ERROR, INPUT, derivePDA, parseU64, SLEEP
+**LISP Forms**: define, const, set!, if, while, for, do, when
+**Logic**: not, null?, empty?
+**Arrays**: length, last, range
+**Utilities**: now, log
+**MCP Tools**: See "Your Available MCP Tools" section below for dynamic tools like COUNT, APPEND, etc.
 
 # MCP Tools Reference
 
@@ -892,7 +893,7 @@ getClusterNodes, getTransaction, monitorTransaction, MEAN, COUNT
 - Nest IF/THEN/ELSE inside loops for conditional logic
 - Use DECISION/BRANCH for multi-way strategy selection
 - Always include time estimates and confidence scores
-- Handle edge cases with GUARD statements
+- Handle edge cases with if-checks and error handling
 - For any RPC method not listed above, use solana_rpc_call(method: "method_name", params: [array_of_params])
 - RPC proxy is case-sensitive: method names must match exactly (e.g., "getBlockTime", not "getblocktime")
 - Params must be passed as an array, even for single parameters