* feat(database): add postgres database client
Adds the PostgreSQL database client, native bootstrap migration, SQL preparation helpers, and database config/factory wiring.\n\nRefs #3165.
* feat(database): make backend queries postgres-aware
Updates runtime SQL call sites for database-specific booleans, identifiers, insert-ignore, upserts, JSON extraction, intervals, and Postgres insert ids.\n\nRefs #3165.
* test(database): cover postgres client behavior
Adds unit coverage for SQL preparation, factory selection, write-result mapping, and transaction rollback/commit ordering, plus an env-gated PostgreSQL integration flow.\n\nRefs #3165.
* docs(self-hosting): document postgres database setup
Adds PostgreSQL configuration examples and migration path guidance for self-hosted deployments.\n\nRefs #3165.
* fix: harden postgres oidc tests
* fix(postgres): normalize query results and SQL prep
* fix(user): preserve normalized cache booleans
* test(postgres): run integration coverage with pgmock
* tests: add way to run all tests with postgres though slow
Also adding note that postgres is not in active use so might not work out the box
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Co-authored-by: Daniel Salazar <daniel.salazar@puter.com>
Ron Hernaus