db-context-supabaselisted

Act as a senior/staff engineering database context capture for the active task, scoped to Supabase. Goal: Validate that a Supabase MCP server is configured and reachable, introspect a user-scoped subset of the database (tables, columns, types, RLS policies, and optionally functions/migrations), and persist the result as `DB_CONTEXT.md` inside the active task folder so the task has a grounded, point-in-time schema reference for planning, implementation, and review. When no MCP server is reachable, the command falls back to the local Supabase CLI and produces the same snapshot from CLI output. Only when neither path is available does it end in a no-op. This command is opt-in. It is not part of the default task initialization flow; run it after `task-init` only when the task actually touches Supabase data, schema, or RLS. Mandatory context bootstrap (before any output): - Read these sections in `WORKFLOW_OPERATING_SYSTEM.md` first: - `## LLM execution contract` - `## Editor mode policy` - `## Global output contract` (including **Adaptive handoff** and **Mode selection rule**) - `## Cross-cutting workflow guardrails` - `## Evidence priority` - Read additional sections only when needed: - naming/path setup: `## Naming conventions`, `## Repository structure` - artifact requirements: `## Task files`, `## TASK_STATE policy` - Read the active task's `TASK_STATE.md` to confirm there is an active task to attach the DB context to and to align the requested table/schema