docs: add comprehensive documentation for operations

This commit introduces a complete set of documentation files
covering various aspects of the project, including environment
setup, quality checks, command references, and architecture.
The documentation is structured to assist developers and
contributors in understanding the project's configuration,
workflow, and best practices.

Additionally, translations for Simplified and Traditional
Chinese have been added to ensure accessibility for a wider
audience. This enhances the overall usability and
maintainability of the project.

Signed-off-by: Bertrand Yuan <github@bertyuan.com>

1 files changed, 60 insertions, 0 deletions

diff --git a/Documentation/source/operations/environment.rst b/Documentation/source/operations/environment.rst
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+Environment
+===========
+
+Validation Source
+-----------------
+
+Environment validation is defined in ``src/env.js`` with
+``@t3-oss/env-nextjs`` and ``zod``. Empty strings are treated as undefined.
+
+Server Variables
+----------------
+
+.. list-table::
+   :header-rows: 1
+   :widths: 34 44
+
+   * - Variable
+     - Purpose
+   * - ``DATABASE_URL``
+     - PostgreSQL connection string.
+   * - ``RESEND_API_KEY``
+     - Resend API key. Must start with ``re_``.
+   * - ``RESEND_AUDIENCE_ID``
+     - Resend audience identifier.
+   * - ``EMAIL_FROM``
+     - Sender email address.
+   * - ``BETTER_AUTH_SECRET``
+     - better-auth secret. Required in production.
+   * - ``BETTER_AUTH_URL``
+     - Optional explicit auth base URL.
+   * - ``GOOGLE_CLIENT_ID`` / ``GOOGLE_CLIENT_SECRET``
+     - Google OAuth credentials.
+   * - ``GITHUB_CLIENT_ID`` / ``GITHUB_CLIENT_SECRET``
+     - GitHub OAuth credentials.
+
+Client Variables
+----------------
+
+.. list-table::
+   :header-rows: 1
+   :widths: 34 44
+
+   * - Variable
+     - Purpose
+   * - ``NEXT_PUBLIC_UMAMI_URL``
+     - Optional Umami analytics script URL.
+   * - ``NEXT_PUBLIC_UMAMI_WEBSITE_ID``
+     - Optional Umami site identifier.
+
+Skipping Validation
+-------------------
+
+``SKIP_ENV_VALIDATION=1`` can be used for limited local or container workflows.
+Do not rely on it for production builds.
+
+Production Notes
+----------------
+
+Production should use explicit, non-default secrets for Payload and better-auth
+and an explicit public site URL for canonical links and generated metadata.