refactor: remove augmentation system and semantic type matching

Remove the entire augmentation pipeline infrastructure (52 files,
~15,000 lines) and the semantic type matching system. These were
unused middleware layers adding complexity without value.

What was removed:
- src/augmentations/ directory (all augmentation implementations)
- src/augmentationManager.ts (pipeline orchestrator)
- src/types/augmentations.ts, src/types/pipelineTypes.ts
- src/shared/default-augmentations.ts
- Semantic type suggestion (BrainyTypes.suggestNoun/suggestVerb)
- src/utils/typeMatching/ (embedding-based type matcher)

What was preserved by relocating:
- Import handlers (CSV, PDF, Excel) -> src/importers/handlers/
- NeuralImportAugmentation -> src/cortex/neuralImportAugmentation.ts
- Type matching utilities -> heuristic inference in consumers

What was simplified:
- brainy.ts: operations call storage directly (no execute() wrapper)
- IntegrationBase: standalone class (no BaseAugmentation parent)
- BrainyTypes: validation-only (nouns, verbs, isValid*, get*)
- Pipeline: direct execution (no augmentation interception)
- index.ts: removed TypeSuggestion, suggestType exports
- package.json: removed stale types/augmentations export

Build passes, 1176 tests pass, 0 failures.

src/cli/commands/core.ts

@@ -148,21 +148,9 @@ export const coreCommands = {
         }
         nounType = options.type as NounType
       } else {
-        // Use AI to suggest type
-        spinner.text = 'Detecting type with AI...'
-        const suggestion = await BrainyTypes.suggestNoun(
-          typeof text === 'string' ? { content: text, ...metadata } : text
-        )
-        
-        if (suggestion.confidence < 0.6) {
-          spinner.fail('Could not determine type with confidence')
-          console.log(chalk.yellow(`Suggestion: ${suggestion.type} (${(suggestion.confidence * 100).toFixed(1)}%)`))
-          console.log(chalk.dim('Use --type flag to specify explicitly'))
-          process.exit(1)
-        }
-        
-        nounType = suggestion.type as NounType
-        spinner.text = `Using detected type: ${nounType}`
+        // Default to Thing when no type specified
+        nounType = NounType.Thing
+        spinner.text = `No type specified, using default: ${nounType}`
       }
       
       // Add with explicit type