v0.9.0: Control Flow & Flow Variables

v0.9.0 — Control Flow & Flow Variables

New Nodes (6)

• ctl.if — Conditional branching with true/false output ports
• ctl.loop.count — Repeat body N times, adds _iteration column
• ctl.loop.chunk — Split input into chunks, adds _chunk column
• ctl.try.catch — Error handling with catch pipeline reference
• xf.variable.set — Extract value from upstream into a flow variable
• xf.variable.get — Emit flow variable as single-row table

Stats

• 42 ML nodes (was 36)
• 386 total MCP components (was 380)
• 143 lib tests pass
• 10 new unit tests for control flow nodes

Bug Fixes

• Stage cache race condition fix (re-verify .exists() at rewrite point)
• Fixed double-quoting in control flow SQL generation
• Fixed flow variable value extraction (any column name)
• Fixed if-branch false view naming consistency

Roadmap

• v1.0.0 — Data Science Platform (Python scripting, Text Mining, Association Rules, more charts, interactive widgets, reporting)
• v1.1.0 — Enterprise & Advanced (Streaming, XAI/SHAP, REST API, Git integration, components)