fix: critical bugs and error handling improvements

lib/config.ts

@@ -243,6 +243,13 @@ export function validateConfigTypes(config: Record<string, any>): ValidationErro
                 actual: typeof config.turnProtection.turns,
             })
         }
+        if (typeof config.turnProtection.turns === "number" && config.turnProtection.turns < 1) {
+            errors.push({
+                key: "turnProtection.turns",
+                expected: "positive number (>= 1)",
+                actual: `${config.turnProtection.turns}`,
+            })
+        }
     }
 
     // Commands validator
@@ -326,6 +333,16 @@ export function validateConfigTypes(config: Record<string, any>): ValidationErro
                     actual: typeof tools.settings.nudgeFrequency,
                 })
             }
+            if (
+                typeof tools.settings.nudgeFrequency === "number" &&
+                tools.settings.nudgeFrequency < 1
+            ) {
+                errors.push({
+                    key: "tools.settings.nudgeFrequency",
+                    expected: "positive number (>= 1)",
+                    actual: `${tools.settings.nudgeFrequency} (will be clamped to 1)`,
+                })
+            }
             if (
                 tools.settings.protectedTools !== undefined &&
                 !Array.isArray(tools.settings.protectedTools)
@@ -497,6 +514,17 @@ export function validateConfigTypes(config: Record<string, any>): ValidationErro
                     actual: typeof strategies.purgeErrors.turns,
                 })
             }
+            // Warn if turns is 0 or negative - will be clamped to 1
+            if (
+                typeof strategies.purgeErrors.turns === "number" &&
+                strategies.purgeErrors.turns < 1
+            ) {
+                errors.push({
+                    key: "strategies.purgeErrors.turns",
+                    expected: "positive number (>= 1)",
+                    actual: `${strategies.purgeErrors.turns} (will be clamped to 1)`,
+                })
+            }
             if (
                 strategies.purgeErrors.protectedTools !== undefined &&
                 !Array.isArray(strategies.purgeErrors.protectedTools)

lib/messages/inject.ts

@@ -274,7 +274,7 @@ export const insertPruneToolContext = (
             contentParts.push(renderCompressNudge())
         } else if (
             config.tools.settings.nudgeEnabled &&
-            state.nudgeCounter >= config.tools.settings.nudgeFrequency
+            state.nudgeCounter >= Math.max(1, config.tools.settings.nudgeFrequency)
         ) {
             logger.info("Inserting prune nudge message")
             contentParts.push(getNudgeString(config))

lib/strategies/purge-errors.ts

@@ -39,7 +39,7 @@ export const purgeErrors = (
     }
 
     const protectedTools = config.strategies.purgeErrors.protectedTools
-    const turnThreshold = config.strategies.purgeErrors.turns
+    const turnThreshold = Math.max(1, config.strategies.purgeErrors.turns)
 
     const newPruneIds: string[] = []