feat: Add workflow examples from AutoMetabuilder

Add 19 example workflow packages demonstrating various patterns:

Templates:
- blank: Empty starter template
- single_pass: Single AI request with tool execution
- iterative_loop: AI loop until completion
- contextual_iterative_loop: Loop with repository context
- plan_execute_summarize: Planning and execution pattern

Data Processing:
- data_processing_demo: Filter, map, reduce operations
- conditional_logic_demo: Branching logic
- repo_scan_context: Repository scanning

Plugin Test Suites:
- dict/list/logic/math/string_plugins_test: Unit tests for plugins

Infrastructure:
- backend_bootstrap: Initialize backend services
- default_app_workflow: Full application workflow
- web_server_bootstrap/json_routes: Flask server setup

Specialized:
- game_tick_loop: Game loop pattern
- testing_triangle: CI/CD test pipeline

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

workflow/examples/python/string_plugins_test/package.json

@@ -0,0 +1,16 @@
+{
+  "name": "string_plugins_test",
+  "version": "1.0.0",
+  "description": "meta.workflow_packages.string_plugins_test.description",
+  "author": "AutoMetabuilder",
+  "license": "MIT",
+  "keywords": ["testing", "string", "unit-test"],
+  "main": "workflow.json",
+  "metadata": {
+    "label": "meta.workflow_packages.string_plugins_test.label",
+    "description": "meta.workflow_packages.string_plugins_test.description",
+    "tags": ["testing", "string", "unit-test"],
+    "icon": "workflow",
+    "category": "testing"
+  }
+}