feat(schema): column names on ClickHouse and a casing table option - #109

A ClickHouse column cannot have a database name apart from its key, and no table can derive its column names from a casing rule. Postgres had PG.column(type, { name }) only.

Closes #87.
Part of #52.

Changes

• CH.column(type, { name: "org_id" }), as PG.column has. The DDL (columns, ORDER BY, PRIMARY KEY, PARTITION BY, indexes, defaults), queries, inserts, ALTER TABLE ... UPDATE, lightweight deletes and the tenant scope write the database name. Rows decode under the key.
• A casing table option, "snake_case" or "camelCase" (new Casing type on both entries), on CH.table and PG.table, managed and external. It names every column that gives no name. A column's own name wins.
• The casing rule is drizzle-orm's, word for word (orgId and OrgId → org_id, HTTPStatus → http_status, address2 stays). So a schema drizzle-kit made with casing: "snake_case" keeps its names.
• The names are fixed where the table is defined, on each column's sqlName. The builder sees only names, so decoding still reads the exact alias it wrote (the note in design/gap-review.md P2).
• A ClickHouse materialized view whose target renames a column records a definition problem. ClickHouse fills the target by database name, and the view's SELECT names its output by key.
• Docs: a "Column names" section in docs/tables-and-types.md (backed by a docs example test), docs/reference.md, and the gap review. One minor changeset.

Left out

• Table @@map: the first argument of table is already the database name, and the variable is the TypeScript name. No table name is a key anywhere in the API. The docs now say so.
• A global casing option: it would need state outside the table, and the builder must not know casing. A project can wrap table in its own function.
• A materialized view into a target with renamed columns: refused with a problem, not rewritten. It can come later, if it is wanted.
• Tinybird datasources: they map columns by JSON path, so no change.
• effect-orm pull still writes the database names as keys. A --casing flag for pull can come later.
• SQLite, MySQL and D1: not on upstream main.

Validation

• bun run build: pass.
• bun run typecheck: pass.
• EFFECT_ORM_CLICKHOUSE_URL=http://127.0.0.1:8123 EFFECT_ORM_CLICKHOUSE_USER=maple EFFECT_ORM_CLICKHOUSE_PASSWORD=maple bunx vitest run --testTimeout=60000 --hookTimeout=60000: 62 files, 1047 tests passed, 0 skipped, on ClickHouse 26.8.2.7. The new tests/column-names.clickhouse.test.ts creates a cased table, a renamed column and a materialized view from their own DDL, and checks system.columns.
• node scripts/check-doc-citations.mjs, node scripts/check-exports-documented.mjs, node scripts/check-doc-examples.mjs: pass.
• bun scripts/check-package.ts: pass.
• Upstream CI for fork PRs waits for a maintainer to approve the run.

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