Fix double-encoded jsonb breaking dream cycle slug lookup

[joelwp]

Summary

• Bug: persistToolExecPending/Failed/Complete in subagent.ts call JSON.stringify(input) before passing to a $N::jsonb parameter. When input is already an object, this produces a JSON string which ::jsonb stores as a jsonb scalar — not a jsonb object. Downstream queries like input->>'slug' then return NULL.
• Symptom: Dream cycle synthesize phase always reports pages_written: 0 even when subagents successfully write pages via brain_put_page. The summary page shows "Pages written: 0" despite pages existing in the DB.
• Same bug in patterns.ts slug collection query.

Fix

1. Root cause (subagent.ts): Skip JSON.stringify when input/output is already a string, preventing future double-encoding.
2. Query fix (synthesize.ts, patterns.ts): Use COALESCE(input->>'slug', (input #>> '{}')::jsonb->>'slug') to handle both old double-encoded rows and new properly-encoded rows.

Files changed

• src/core/minions/handlers/subagent.ts — persist functions
• src/core/cycle/synthesize.ts — collectChildPutPageSlugs
• src/core/cycle/patterns.ts — same query pattern

Test plan

• Run gbrain dream --date <date> with existing double-encoded rows — summary should now show correct page count
• Run a new dream cycle — verify subagent_tool_executions.input is stored as jsonb object (not scalar string)
• Verify input->>'slug' returns the slug for both old and new rows

🤖 Generated with Claude Code

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