docs: revamp docs

[calvinbrewer]

A much needed docs update which removes the language favoring CipherStash Proxy, and instead focuses on EQL specifically. Also includes instructions for publishing to dbdev.

[Copilot]

Pull Request Overview

This PR refactors the documentation to center on EQL instead of CipherStash Proxy, removes legacy tutorial and reference files, and adds support for publishing the extension to dbdev.

• Introduces a new postgres:psql task and updates the build script to emit a dbdev SQL artifact.
• Removes old Proxy and Getting Started tutorials, replacing them with an EQL-specific Proxy configuration guide.
• Updates documentation navigation and adds dbdev publishing instructions in DEVELOPMENT.md; adjusts reference pages accordingly.

Reviewed Changes

Copilot reviewed 14 out of 16 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
tasks/postgres.toml	Added postgres:psql task but did not use the computed default_service.
tasks/build.sh	Appends dbdev SQL output but includes an unintended trailing backslash.
docs/tutorials/proxy-configuration.md	New EQL-focused Proxy configuration tutorial.
docs/tutorials/PROXY.md	Removed old Proxy tutorial.
docs/tutorials/GETTINGSTARTED.md	Removed old Getting Started guide.
docs/reference/index-config.md	Clarified Proxy context and added Protect.js note.
docs/reference/PAYLOAD.md	Removed redundant schema reference.
docs/reference/MIGRATOR.md	Removed old Migrator reference.
docs/concepts/WHY.md	Updated section order to include Protect.js and Getting started.
docs/README.md	Reworked nav to separate Reference and Tutorials; updated links.
README.md	Added dbdev section, renamed integration headers, and updated nav.
DEVELOPMENT.md	Added dbdev publishing instructions.

Comments suppressed due to low confidence (1)

docs/README.md:11

• The filename index-config.md does not match the link index-configuration.md; please ensure the file and its link are consistently named to prevent broken references.

- [EQL index configuration for CipherStash Proxy](reference/index-configuration.md)