build: update dependencies, switch to prek and go-overlay

[tembleking]

Updates all dependencies, bumps the version to 2.0.2 for release, and migrates the Go toolchain source to go-overlay.

Why drop nixos-25.11 for Go?

In #84 we pinned go_1_26 to nixos-25.11 because there it wasn't the latest stable Go (1.25 was), so it had few reverse dependencies and got updated within hours of an upstream release.

That no longer works: nixos-25.11 is now a frozen stable release channel, so its Go toolchain won't move forward anymore — staying on it means getting stuck on an increasingly outdated Go. nixpkgs-unstable isn't a fix either: there the latest-stable Go is a dependency of many packages, so a bump has to clear the whole test/rebuild pipeline before landing — typically ~3 weeks between a Go release and it being usable.

go-overlay removes both problems: it tracks upstream Go releases and updates within hours, independent of the nixpkgs rebuild cycle, so we always build against the current toolchain.

Why prek instead of pre-commit?

prek is a drop-in pre-commit reimplementation in Rust: same .pre-commit-config.yaml, no Python/virtualenv bootstrap, faster install and parallel hook execution, and a smaller on-disk footprint.

[Copilot]

Pull request overview

This PR prepares the sysdig-mcp-server for release 2.0.2 by updating Go/Nix dependencies and evolving the development toolchain: it switches the Go toolchain sourcing to go-overlay and replaces pre-commit usage with prek while keeping the existing .pre-commit-config.yaml workflow.

Changes:

• Bump package version to 2.0.2 and refresh vendorHash.
• Update Go module dependencies (mcp-go, ginkgo/gomega, x/net, x/tools) and refresh go.sum.
• Update Nix flake inputs/lock to use go-overlay, and replace pre-commit commands with prek in dev tooling + docs.

Reviewed changes

Copilot reviewed 8 out of 10 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
package.nix	Switch build function to buildGoLatestModule, bump version to 2.0.2, update vendorHash.
flake.nix	Add go-overlay, introduce go_latest + override buildGoLatestModule, and switch dev shell hook/tooling to prek.
flake.lock	Update lockfile for new inputs (notably go-overlay) and refreshed nixpkgs pins.
go.mod	Bump Go dependencies to newer versions.
go.sum	Sync checksums with the updated module graph.
justfile	Replace pre-commit autoupdate with prek autoupdate.
docs/TROUBLESHOOTING.md	Update troubleshooting instructions from pre-commit to prek.
AGENTS.md	Update developer handbook section to refer to prek instead of pre-commit.
docker-base-amd64.nix	Refresh pinned base image digest/hash for amd64.
docker-base-aarch64.nix	Refresh pinned base image digest/hash for aarch64.

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