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+---
+title: "freeform project_id BIGINT 对齐 projects.id"
+task_id: "freeform-project-id-bigint-2026-09-22"
+status: done
+created: 2026-09-22
+owner: Cursor
+task_type: implementation
+branch: feature/freeform-project-id-bigint-2026-09-22
+worktree: .worktrees/freeform-project-id-bigint-2026-09-22
+write_scope: ["deploy/postgres/goose", "internal/freedoc", "internal/server", ".doc"]
+allowed_environments: ["dev"]
+mutex: "deploy/postgres/goose + freeform"
+---
+
+# freeform project_id BIGINT
+
+## 问题
+`POST /api/v1/freeform-documents` 在雪花 `project_id`（>int4 max）时 pgx 编码失败（OID 23），阻塞 UI-11 附件注册。
+
+## 修复
+- goose `00063`：`freeform_documents.project_id` → BIGINT
+- Go `ProjectID`/`ListDocuments` → int64；list query 用 `ParseInt`
+- 活库已手工 ALTER（schema 仍报 61）；合入后 goose 幂等加固
+
+## 验证
+- `go test ./internal/freedoc/ -short` PASS（含 snowflake 回归）
+- 活库 column = bigint